If you never bluffed...

I've been playing limit Holdem at 1/2 & 2/4 for a few months now with limited success (1.9BB/100). I started playing two tables at once a week ago and I noticed that:
1. My pre-flop play was tighter
2. I was more willing to fold
3. I virtually never bluffed anymore
4. My winnings so far seem to be the same as usual.
My question is - how successful can poker player be playing tight-agressive-sensible but NEVER BLUFFING?! What would happen?<font color="green"> </font>