so this could be totally discounted due to me being pretty low level.
I'm a silver league protoss, doing my thing, trying to make it in the lower leagues, doing my thing, refining mechanics, et cetera.
However, I went through a month-long spell of just not feeling like laddering at all, so when I got back into it, I got bumped down to bronze. My thoughts were that I'd play a few games, probably win a good percentage of them, and soon be back playing against players around my actual skill level. What I didn't realize was how this would help me with some major mental handicaps I'd been giving myself.
The first is my willingness to Just Go Kill Them. I am now far more confident in my ability to be aggressive successfully, especially in the mid-game and late-game, where my prior thought process had been "oh, I can probably defend their coming push. Let's turtle some more and tech up and get more units and upgrades."
The second, and probably the more important, is my confidence in my own ability to expand. Where previously, I had been very much tentative in taking any bases beyond my natural, due to fear of them being killed off, I am now much more comfortable going up to 3 or 4 bases significantly earlier.
TL;DR: Confidence is an important part of starcraft and being bumped down from silver to bronze is really helping me on this front. Just an interesting thought I felt like sharing.