I find it fascinating too how games at this level play off. But what's even more interesting is talking to those people !
I've chatted once with RoyBatty6, one of the gatekeepers of ~500 elo. He only plays ranked 1v1, about hundred of hours per month acocrding to the leaderboard ... I was curious why he never plays anything else, and if he actually was trying to improve his strategies after so many games.
He just told me about playing a teamgame long ago, and not knowing what to do, while people expected him to play a certain way. So he felt quite "unprepared" to play teamgames and just focuses on 1v1 ! We talked about general strategies, which ones he struggles against ( i recall he mentionned turtle ..) ... and he actually asked me for advices !
I have a feeling that he just doesn't care too much about how the game should be played but just enjoys playing it his own way, which is great. Sometimes I wish those guys were more under the spotlight, we don't hear from them too much, even tough we can clearly spot some legends just looking at the leaderboard.
Watching replays from other players at this level is so interesting cause you have numerous playstyles and they do just so many random things with a crazy consistency ! Maybe that would call for a cast of "low elo legends" like they do in some other RTS communities ?