maybe you know this, maybe you don't....if you do, please add. if you don't, please give it a try.
wanna corner waaaaay better and faster? of course you do.
if you are like most cyclists, when you corner, you learned to stick your knee waaay out.
however, this is not efficient.
the way to corner is....keep the top half of your body straight, keep your knee inside, touching your top tube, and push down on your handlebars, looking through the turn. your bike will be leaning, your upper body straight, it feels and looks goofy but you can make way tighter turns. this also works on the road when coming downhill. it's scary at first, but when you get the hang of it, you can take turns waaay faster than you should and you live to tell about it.
a good way to practice this is in a parking lot (or grassy knoll) with a traffic cone (or any obstacle to get around). ride at it, then exaggerate the lean of the bike and turn/corner around the obstacle with your inside knee touching the top tube, the top half of your body straight, your bike leaned, your head looking through the turn (like a switchback).
you can do this seated as well as crouched.
(no reason for posting this, just wanted to share and post something that isn't a "what bike should i buy" thread)