I'm a 33 minute 10ker...so not "fast" but I'm not a slouch.
The sad truth is that there are two things that would make me faster
1. Losing Weight
2. Running more miles.
At 6'2", 162ish, I'm a little soft around the middle. I'm just not willing to make the sacrifices to get down to 150.
99% of the general population would say I'm skinny. When I see elites or near elites at road races, I understand why I'm minutes behind.