Scott's serve is very good. If he were say 6'2 his serve would be ridiculous.
And OSU, although he doesn't hit it 120, he places it on a dime and always seems to get an incredible amount of 1st serves in.
For me the serve is just an "athletic" stroke where it always just came naturally to me. I wish I could say that about the fh volley and backhand. But to me the serve is all about rhythm and timing though I guess you can say that about all strokes. Being 6'4 with long arms is a big plus, no denying that. If all else fails just toss er up, close yer eyes, and let er rip.