This would contribute to debugging in a major way because without first knowing what works you can not determine what is broken. Getting a project to a state where it is running at the proper frame rate and then re-enabling options one by one to see which options or combination of options causes the issues gives us a better idea of what is happening in between builds. If for **EXAMPLE **(This is **PURELY **for example sake as I have no data that would otherwise back this up) you find that enabling bloom causes FPS issues on 4.9 but did not in 4.8, we can then look at that code, see what changed were made and why that is affecting VR. Just simply saying that the performance in 4.9 is worse than the performance in 4.8 gives me nothing to go on, I need more data than that to make a case about performance.