[ludo72]

I think both questions largely depend on how often you raise pre-flop in general or how your opponents view your raising standards. If someone only raises pre-flop with AA-QQ and AK, he should obviously c-bet every flop, because his handrange will hit the flop so often it wouldn't make any sense to start playing back at his flop bets without a real hand. On the other hand if you raise with half of your hands, betting the flop everytime is probably not a wise idea because no sane player will give your flop bets any respect after a while.

So in conclusion I will bet or check depending on my table image and how much credit my opponents are giving to me.