I've never overclocked anything and I've never felt I've missed out in any way. I really can't imagine spending even one minute trying to squeeze 5% or whatnot tweaking voltages and dealing with plumbing and roaring fans. I want to use the machine, not hotrod it.
I would rather Intel et al. leave a few percent "on the table" and sell things that work, for years on end without failure and without a lot of care and feeding. Lately it looks like a crapshoot trying to identify components that don't kill themselves.