I see a lot of posters on this board claiming they hit aces on a regular basis in their matches. The problem is, I just don't see it in real life. There are a few tall guys with big serves and weak groundstrokes who can do it, but from what I see, aces just don't happen more than a couple times a match. I figure maybe adults are different from juniors (because they've spent more time honing their placement and can't move as well to return well-placed serves), but I've watched decent adult players play and don't see many aces there either. Anyone want to share some observations?