A mate used to always tell me you should never bet against yourself, that is to say if you have a side to win on one line you shouldn't pick them to draw or lose on another.
I know things are different on Betfair (which I don't pretend to understand) where you can back and lay at different prices to limit losses or better but what about this as a general rule, especially for a small stakes punter?
I've seen a few bets listed on here where posters appear to be effectively betting against themselves.