the olde google trick for 'backclipping' yielded: http://www.altrec.com/published/climb/skills/backclipwhat/ complete with pictures an shit.
bent gate biners are said to be more likely to have the rope open the gate and come out altogether. i have seen this demonstrated many times by smartasses at the gear shops and in the crag parking lots. personally i dont see how 99% of the falls a climber might take out generate such a weird whip against the gate even if you backclipped. and btw i used to climb with a very competent dude who preferred the 'backclipped' orientation. fukin semantics.