I'm 5'11" with a "junk height" of about 33". That said, I ride a 58 cm Raleigh, ww.5" (57 cm) Univega and a 61 cm Peugeot. All of them "fit" me (i.e. they're comfy, and I could ride them forever) as I have them set up (the Uni has NR bars - drops might be a bit too short), yet the lads are comfortably touching, if that makes sense, on the Raleigh and Unis, the Peugeot is rather uncomfortable to stand over, but I can *kinda* do it flat footed...

Anyway, all that is to say that it doesn't really seem to matter as long as you don't go crazy on it. For instance, even though I could probably ride 63cm, I don't know if I would, and if I go much smaller, I find I'm crouching too much.