Diagnostic selector

Measured problem	First inspection	Route
GPU cost scales strongly with resolution	profilegpu, pass event tree	TSR/resolution, pixel-heavy pass
Draw/Render thread dominates	Primitive Debugger, stat sceneRendering, primitive/section counts	submission/culling/LOD
BasePass high	Shader Complexity, material/primitive isolation	materials/overdraw
Translucency/post high	Shader Complexity, screen coverage, effect toggles	translucency/resolution
Nanite pass/streaming issue	Nanite visualization, NaniteStats	Nanite geometry
Lumen GI/reflection high	Lumen overview/visualizations, quality A/B	Lumen
Shadow Depths/Projection high	VSM cache/caster views, light isolation	VSM or MegaLights
many local lights/noisy direct light	MegaLights light/ray/caster visualizers	MegaLights
TSR cost or ghosting	Temporal Upscaler visualization, GPU event	TSR
GPU memory over budget	Render Resource Viewer, RHI/platform memory stats	resources/streaming
camera-cut spike	GPU/Timing trace, VSM/visibility/streaming evidence	subsystem causing burst

Disable diagnostic views before the timed A/B capture. Their value is attribution, not the final number.