Eeet DO, Eeet DO!
Ummm at 4.2 @ 1.294 vcore I was hitting 79-79-76-76 under LinX and hitting 72-72-68-68 under Prime 95.
The proof is in the pudding and the hardware was exactly the same before and after (same TIM, fans, ambient, mounting). Just take your time doing it and you can't go wrong I was shocked when I seen the difference.
I'm on the fence about lapping the CPU, but I never had a CPU die on me so it's tempting to do.