I don't mind bumpdrafting at all, if it's done safely, i.e. on straights only and if no pass is attempted, the bumping car backs off early enough. I do it often on BL1 w/ XFG when catching up with the leaders or trying to outrun someone i know is faster. I do it safely, and can't remember a time it's ever resulted in a lag crash. In fact, I see it as not wanting to catch up with leaders if it's not done when possible (wtf, you want to lose eh?).
@the ppl who brake in front of bumpdrafters:
That's wrecking/blocking (depending on the outcome), deliberately slowing the other car down or taking it out. Bumpdrafting is not wrecking and when practised correctly is beneficial to both racers involved. What justifies you to wreck instead of informing you don't approve of this? I bet most BDs including me will back off and won't try it again with you.
The same as a flame: You brakers are a sad lot of losers, rubbing in racing is everyday stuff when done with cars that can handle it. Take your head out of your ass and see it does wonders for both of you.