I did some testing and what RealNC said is absolutely right, thank you. Without "1/2 Refresh Rate" (only normal 60Hz Vsync + 30FPS lock in RTSS) there is, indeed, smaller input lag that way, but there is always some micro stutter, regardless of what kind of precise ~30 FPS limit I set. I was testing that with a controller in few games by panning the camera around me at a constant rate. Sometimes I was able to make the whole "circle" fine, but most of the times there was one or two "angles" at which the game would stutter slightly, even though FPS stayed dead stable. It's very subtle stutter, some people might not even notice it, but it's there. However, With "1/2 Refresh rate" Vsync from NVIDIA Inspector, the micro stutter is removed entirely, but obviously, there is higher input lag. But it's super smooth, no micro stuttering at all. Using the -0.01 adjustment indeed helps with reducing input lag, but it still isn't as responsive as without "1/2 Refresh Rate". But without doubt, this is a far better option for visually smoothest 30FPS. Too bad there's such a big input lag compared to normal VSync, even with -0.01 adjustment, but oh well, it's a trade-off. At least now I can play smoothly the most demanding games in which I wouldn't be able to get such a good frame pacing at 60 FPS due to the slight fluctuations.