diff --git a/apps/electron-backend-e2e/src/journeys/launch-journey-app.ts b/apps/electron-backend-e2e/src/journeys/launch-journey-app.ts
index 24fd41e27..b69633e70 100644
--- a/apps/electron-backend-e2e/src/journeys/launch-journey-app.ts
+++ b/apps/electron-backend-e2e/src/journeys/launch-journey-app.ts
@@ -32,6 +32,10 @@ import {
     assertJourneyMainCounters,
     readJourneyMainCounters,
 } from '../performance/journey-main-counters';
+import {
+    journeyLaunchEnvironment,
+    type JourneyLaunchInstrumentation,
+} from '../performance/journey-launch-environment';
 import {
     createLaunchJourneyProbeOptions,
     installJourneyRendererProbe,
@@ -129,6 +133,7 @@ export async function measureLaunchJourney(
     const { launch } = await runLaunchJourney(
         templateDirectory,
         timeoutMs,
+        { mainCounters: true },
         async () => undefined
     );
     return launch;
@@ -142,10 +147,13 @@ export async function measureLaunchJourney(
  * therefore in place before the renderer runs any script, and the probe,
  * capture and gate records still prove it. `continueJourney` runs in the
  * same process after J1's counters are final, before the app is closed.
+ * Without `instrumentation.mainCounters` the main-process counters and SQL
+ * counting stay off and `launch.mainCounters` is null.
  */
 export async function runLaunchJourney<T>(
     templateDirectory: string,
     timeoutMs: number,
+    instrumentation: JourneyLaunchInstrumentation,
     continueJourney: (session: LaunchJourneySession) => Promise<T>
 ): Promise<{
     readonly continuation: T;
@@ -156,17 +164,9 @@ export async function runLaunchJourney<T>(
     );
     try {
         await cp(templateDirectory, dataDirectory, { recursive: true });
-        // IPTVNATOR_PERF_CAPTURE turns on the main-process counters and
-        // their read handler, IPTVNATOR_PERF_COUNT_SQL the SQL statement
-        // count behind main.sqlStatementsBeforeReadyToShow; only this journey
-        // sets it. See journey-main-counters.ts.
         const env = buildElectronLaunchEnvironment(
             dataDirectory,
-            launchOptions({
-                IPTVNATOR_PERF_CAPTURE: '1',
-                IPTVNATOR_PERF_COUNT_SQL: '1',
-                IPTVNATOR_TRACE_IPC: '1',
-            })
+            launchOptions(journeyLaunchEnvironment(instrumentation))
         );
         const args = buildElectronLaunchArgs([
             '-r',
@@ -229,13 +229,15 @@ export async function runLaunchJourney<T>(
                 10_000
             );
             // Read after the probe finished, so both frozen counters exist.
-            const mainCounters = assertJourneyMainCounters(
-                await readJourneyMainCounters(
-                    electronApp,
-                    JOURNEY_RENDERER_GATE_KEY
-                ),
-                gate
-            );
+            const mainCounters = instrumentation.mainCounters
+                ? assertJourneyMainCounters(
+                      await readJourneyMainCounters(
+                          electronApp,
+                          JOURNEY_RENDERER_GATE_KEY
+                      ),
+                      gate
+                  )
+                : null;
             if (ipc.installedEpochMs > renderer.installed.epochMs) {
                 throw new Error('journey-main-ipc-capture-installed-late');
             }
diff --git a/apps/electron-backend-e2e/src/journeys/open-source.journey.ts b/apps/electron-backend-e2e/src/journeys/open-source.journey.ts
index 075ab78bb..499e1e016 100644
--- a/apps/electron-backend-e2e/src/journeys/open-source.journey.ts
+++ b/apps/electron-backend-e2e/src/journeys/open-source.journey.ts
@@ -50,6 +50,9 @@ test('J2 open a source', async () => {
                 const { continuation, launch } = await runLaunchJourney(
                     templateDirectory,
                     JOURNEY_ITERATION_TIMEOUT_MS,
+                    // J2 does not read J1's main-process counters, so their
+                    // SQL instrumentation stays off during the click.
+                    { mainCounters: false },
                     (session) =>
                         measureOpenSourceJourney(
                             session,
diff --git a/apps/electron-backend-e2e/src/performance/journey-launch-environment.spec.ts b/apps/electron-backend-e2e/src/performance/journey-launch-environment.spec.ts
new file mode 100644
index 000000000..7dde1bfde
--- /dev/null
+++ b/apps/electron-backend-e2e/src/performance/journey-launch-environment.spec.ts
@@ -0,0 +1,18 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { journeyLaunchEnvironment } from './journey-launch-environment';
+
+test('J1 launches with the main-process counters and SQL counting', () => {
+    assert.deepEqual(journeyLaunchEnvironment({ mainCounters: true }), {
+        IPTVNATOR_PERF_CAPTURE: '1',
+        IPTVNATOR_PERF_COUNT_SQL: '1',
+        IPTVNATOR_TRACE_IPC: '1',
+    });
+});
+
+test('a journey that does not read the main counters launches with the IPC trace only', () => {
+    assert.deepEqual(journeyLaunchEnvironment({ mainCounters: false }), {
+        IPTVNATOR_TRACE_IPC: '1',
+    });
+});
diff --git a/apps/electron-backend-e2e/src/performance/journey-launch-environment.ts b/apps/electron-backend-e2e/src/performance/journey-launch-environment.ts
new file mode 100644
index 000000000..acd9f58af
--- /dev/null
+++ b/apps/electron-backend-e2e/src/performance/journey-launch-environment.ts
@@ -0,0 +1,26 @@
+/**
+ * Instrumentation flags a journey launch sets on the Electron process.
+ *
+ * Every journey needs the renderer-API trace (`IPTVNATOR_TRACE_IPC`) for its
+ * IPC counters. Only J1 records the main-process counters:
+ * `IPTVNATOR_PERF_CAPTURE` turns on the counters and their read handler, and
+ * `IPTVNATOR_PERF_COUNT_SQL` wraps every main-thread and worker SQLite
+ * statement to count it (see journey-main-counters.ts). A journey that
+ * continues from the launch without reading them (J2) leaves both off, so
+ * its latency and workload are not measured under that extra
+ * instrumentation.
+ */
+export interface JourneyLaunchInstrumentation {
+    readonly mainCounters: boolean;
+}
+
+export function journeyLaunchEnvironment(
+    instrumentation: JourneyLaunchInstrumentation
+): Record<string, string> {
+    return {
+        ...(instrumentation.mainCounters
+            ? { IPTVNATOR_PERF_CAPTURE: '1', IPTVNATOR_PERF_COUNT_SQL: '1' }
+            : {}),
+        IPTVNATOR_TRACE_IPC: '1',
+    };
+}
diff --git a/apps/electron-backend-e2e/src/performance/journey-main-counters.spec.ts b/apps/electron-backend-e2e/src/performance/journey-main-counters.spec.ts
index 34684c01d..51caeb3ae 100644
--- a/apps/electron-backend-e2e/src/performance/journey-main-counters.spec.ts
+++ b/apps/electron-backend-e2e/src/performance/journey-main-counters.spec.ts
@@ -143,5 +143,10 @@ test('only the launch journey opts into SQL statement counting', () => {
             )
         )
         .map((file) => relative(sourceRoot, join(sourceRoot, file)));
-    assert.deepEqual(optedIn, [join('journeys', 'launch-journey-app.ts')]);
+    // The journey launch builds its flags in one place, and only the
+    // launch journey asks for the main counters there (J2 launches with
+    // `mainCounters: false`; see journey-launch-environment.spec.ts).
+    assert.deepEqual(optedIn, [
+        join('performance', 'journey-launch-environment.ts'),
+    ]);
 });
diff --git a/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.spec.ts b/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.spec.ts
index fe6efa696..13723485c 100644
--- a/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.spec.ts
+++ b/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.spec.ts
@@ -87,6 +87,7 @@ test('forwards every request to the mock and records it from a mark', async () =
         ]);
         const mark = ledger.mark();
         assert.equal(mark, 1);
+        const beforeSecond = performance.timeOrigin + performance.now();
         const second = await fetch(
             `${ledger.origin}/player_api.php?username=u&password=p&action=get_account_info`
         );
@@ -103,6 +104,10 @@ test('forwards every request to the mock and records it from a mark', async () =
         );
         assert.equal(since[0]?.method, 'GET');
         assert.equal(since[0]?.sequence, 1);
+        // Stamped on the same high-resolution epoch as the renderer's click.
+        const stamped = since[0]?.epochMs ?? 0;
+        assert.ok(stamped >= beforeSecond);
+        assert.ok(stamped <= performance.timeOrigin + performance.now());
         assert.ok(!JSON.stringify(ledger.since(0)).includes('password'));
     } finally {
         await ledger.close();
diff --git a/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.ts b/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.ts
index 7336e5708..f63a679a4 100644
--- a/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.ts
+++ b/apps/electron-backend-e2e/src/performance/journey-mock-request-ledger.ts
@@ -23,6 +23,12 @@ import type { AddressInfo } from 'node:net';
  * never stored.
  */
 export interface JourneyMockRequest {
+    /**
+     * Arrival as a sub-millisecond epoch (`performance.timeOrigin +
+     * performance.now()`), the same form as the renderer's click stamp. With
+     * `Date.now()` a request later in the click's millisecond would compare
+     * as earlier than the fractional click and be counted before it.
+     */
     readonly epochMs: number;
     readonly method: string;
     readonly route: string;
@@ -94,7 +100,7 @@ export async function startJourneyMockRequestLedger(
             active -= 1;
         });
         requests.push({
-            epochMs: Date.now(),
+            epochMs: performance.timeOrigin + performance.now(),
             method: incoming.method ?? 'GET',
             route: describeJourneyMockRoute(incoming.url),
             sequence: requests.length,
diff --git a/apps/electron-backend-e2e/src/performance/launch-journey-record.spec.ts b/apps/electron-backend-e2e/src/performance/launch-journey-record.spec.ts
index e1df24260..168b59348 100644
--- a/apps/electron-backend-e2e/src/performance/launch-journey-record.spec.ts
+++ b/apps/electron-backend-e2e/src/performance/launch-journey-record.spec.ts
@@ -155,6 +155,13 @@ test('rejects measurements whose clocks or probes are inconsistent', () => {
             }),
         /incomplete-probe/
     );
+    // A launch that ran without the main-process counters (as J2's do) is
+    // not a J1 measurement.
+    assert.throws(
+        () =>
+            toLaunchIterationRecord(0, false, { ...base, mainCounters: null }),
+        /main-counters-missing/
+    );
     assert.throws(
         () =>
             toLaunchIterationRecord(0, false, { ...base, spawnEpochMs: 2_700 }),
diff --git a/apps/electron-backend-e2e/src/performance/launch-journey-record.ts b/apps/electron-backend-e2e/src/performance/launch-journey-record.ts
index b2ce47508..2ebae4c26 100644
--- a/apps/electron-backend-e2e/src/performance/launch-journey-record.ts
+++ b/apps/electron-backend-e2e/src/performance/launch-journey-record.ts
@@ -45,7 +45,8 @@ export interface LaunchJourneyMeasurement {
     readonly electronVersion: string;
     readonly gate: JourneyRendererGateState;
     readonly ipc: JourneyMainIpcCaptureState;
-    readonly mainCounters: JourneyMainCountersState;
+    /** Null when the launch ran without the main-process counters (J2). */
+    readonly mainCounters: JourneyMainCountersState | null;
     readonly pid: number;
     readonly renderer: JourneyRendererProbeState;
     readonly spawnEpochMs: number;
@@ -61,6 +62,9 @@ export function toLaunchIterationRecord(
     measurement: LaunchJourneyMeasurement
 ): JourneyIterationRecord {
     const { ipc, mainCounters, renderer, spawnEpochMs } = measurement;
+    if (mainCounters === null) {
+        throw new Error('launch-journey-record-main-counters-missing');
+    }
     if (renderer.terminal === null || renderer.navigation === null) {
         throw new Error('launch-journey-record-incomplete-probe');
     }
diff --git a/docs/architecture/performance-journeys.md b/docs/architecture/performance-journeys.md
index c6b6fc15e..b7ea4dc41 100644
--- a/docs/architecture/performance-journeys.md
+++ b/docs/architecture/performance-journeys.md
@@ -120,8 +120,9 @@ registers the `performance:read-counters` IPC handler. Without the flag
 nothing is counted, no listener is attached and the handler does not exist;
 the preload never exposes the channel. SQL statements are counted only with
 `IPTVNATOR_PERF_COUNT_SQL=1` as well, because the hook wraps every statement
-execution: the journey sets both, while the M3U, refresh and Xtream
-benchmarks run with the capture flag alone and keep measuring unwrapped
+execution: the launch journey sets both (the flags are built in
+`journey-launch-environment.ts`), while J2's launches and the M3U, refresh
+and Xtream benchmarks do not set the SQL flag and keep measuring unwrapped
 statements. A harness test fails if any other source sets the SQL flag. After the renderer probe completes,
 `journey-main-counters.ts` calls the handler through `electronApp.evaluate`
 and the gate's tap.
@@ -247,7 +248,11 @@ running app to `measureOpenSourceJourney` in
 `src/journeys/open-source-journey-app.ts`. The click therefore happens after
 J1's terminal condition and its counters are final, and the two journeys never
 overlap. One warm-up and five measured iterations, as for J1; the J1 numbers
-of these launches are not reported again.
+of these launches are not reported again. J2 does not read J1's
+main-process counters, so its launches run without `IPTVNATOR_PERF_CAPTURE`
+and `IPTVNATOR_PERF_COUNT_SQL` (`runLaunchJourney` with
+`mainCounters: false`). The click is not measured under the SQL hook that
+wraps every statement.
 
 **Start.** The click on the dashboard card of the Xtream portal
 (`dashboard-recent-sources-rail-card` with the portal's name; the probe also