Every time I think it's the bike that's holding me back all I have to do is go riding (and get my butt handed to me royally) with the skinny kid on the rigid single speed...
Yep. After ungracefully picking my way down Goat's Gully (at Whistler Bike Park) on my 8" dual squish I watched a kid just blaze down it on a hardtail like it was nothing. Rider skill (or lack thereof in my case) trumps bike any day.
My bike is pretty slow. It doesn't climb well either. Once I put it at the bottom of the hill and watched, and watched, and watched.....and it didn't move at all.
Seriously, it's not possible to answer the "is full-suspension faster" question in any general way. The answer comes down to a combination of trail conditions the bike you're comparing to. I can think of at least one trail having some stretches I could take fastest on a suspension bike, and other stretches that I could take faster on a road bike. Which bike is faster for me overall? It just depends upon the trail.