You have some legitimate concerns. I think of Olynyk as mobile and coordinated for a big, but I guess that is not the same thing as having speed and quickness.
As I've mentioned before, he's one of these guys who was a point guard in early high school and then sprouted like crazy to turn into a big man. I think he has guard-like offensive feel. He passes really well from what I've seen.
Can he do these moves against real talent?? That is a concern. He put up some great numbers against Baylor, if memory serves.
No, he does not look long at all. I wouldn't be surprised if he measures with an 8'10 reach and a 7'1" wingspan. But he DOES look bulky to me. I think he could be a 4/5.