Yeah, the iffy collisions in online races ruin that a little.
I probably still can't dodge barriers for my life, but that's just me.
The collisions though are a definite drawback to this mode. Fix the lag! There's no reason apart from a bad connection that it should be there. If I can play online FPS without such bad lag, I expect the same level of precision from WipEout HD as I know it is possible.