well, keep in mind he's a sf and mayo is a sg/pg...
Well, I see them both as scoring swingmen. I think CDR's NBA position will be SG, same as Mayo (who I can't see being an effective PG).
The problem I have with CDR is that he's not that great of an athlete, not a very good shooter and, as one can see in that video, his dribbling is quite high and loose. He looked more quick and better playing under Calipari's system than he actually is, I think. After looking at his game during the tournament with further detail, I became very suspicious about his potential to have a NBA career. I think he'll struggle to translate his skillset to the pros and will need to become a very focused and smart defender to overcome his lack of quickness.
I don't get why the trainer was instructing them to travel on that last drill. I realize they're getting ready for the NBA, but don't make it too obvious. 
I understand you're jocking here, but there's actually an awful lot of comments saying the exact same thing about that drill on youtube. It may look that way, but there is no travel violation on that last drill.
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As for Walker dunking, I wouldn't read to much on it. All the other guys could do it quite easily. And his shooting mechanics are so bad it's painful to watch. I'm hoping he has improved his game a lot during this Summer; he wasn't a NBA player when the college season finished.