It's my understanding that locking your fps at 59 would not cause these problems, due to the fact that some people can't maintain 60fps anyway. So wouldn't those people be screwed anyway if their game can only run at say 40fps?
I should have been clearer in my post - I wasn't referring to 60Hz as in 60 frames per second, but rather the refresh rate of your monitor. 60Hz vsync is the only way you can prevent the framerate going over 60 (where wonky physics happen), without using a framerate limiter (which causes the timing in the game to break even if you limit the framerate to 60). See threads here:
http://www.gamesas.com/topic/1321635-delayed-actions/page__hl__delay
http://www.gamesas.com/topic/1327300-arrow-lag-after-shooting
Therefore, the only way to run the game without gameplay glitches is to run at a refresh rate of 60Hz Vsynced (most people's default refresh rate). This brings up another issue when you have a 120Hz monitor, in which case unless you turn your refresh rate down to 60Hz, you're going to get wonky physics and other visual glitches (because the game is running at a max of 120fps). It's all a bit of a clusterf*ck, but all you need to take away is that you NEED to run the game with it's ridiculous dependence on vsync and a 60Hz refresh rate if you don't want issues.
However, this has been complicated because the mouselag and stutter issues people have been experiencing with a 60Hz Vsynced game has encouraged them to turn vsync off and use framerate limiters - perfectly reasonable steps for other games, but precisely what will cause gameplay issues (which are worse than visual issues IMO) in this game.
I'm also noticing that I no longer CTD when playing the game with default vsync and with no framerate limiters, but it could be unrelated.