Whilst it is not impossible for them to do so, the reality is that with modern machines you are very unlikely to see any difference at all.
The main reason, I think, is that there is just so much going on with so many different processes that any minor tweaks get drowned out in all that noise.
You are much more likely to see an effect by tweaking the running services.
On old machines and with older versions of Windows, this may be different. Even so, the biggest impact is how many services you have running, whether you have the best possible video (and other) drivers and, perhaps, most of all, whether you have sufficient resources (primarily memory).