I see way too much buffing and out right Poker Bully strategy on Replay.
I think part of the reason is because there is no real risk on a free chip site and the other is players enable that strategy by trying to out-bluff and bully the bullies.
There is a time when a semi-bluff is appropriate when you have a possible and you think your opponent may have a weak hand or you hold high cards and think you might win with a kicker on the river.
Other than that- bluffing as a strategy is probably not going to pay off against more advanced players that will read your bluffs and call.
ADDED: I wrote a much more detailed guide to bluffing here: