A safer variation on the OP's strategy which works well for me - let's say you limp into a multiway pot with no raises preflop (eg sc's late or on the BB) and don't improve with the flop. If everyone checks the flop then bet the turn - you have a very high chance of taking the pot down.

Basically stealing on the flop is suspicious when you haven't shown strength preflop. Turn bets gets much more respect and the lack of other bets suggests no-one has a hand.