Coaches may take note if they happen to have a stop watch and are honed in on a particular player. It sounds like your son has more gas in the tank however. Going from a 7.5 to 7.0 is impressive. Encourage him to keep working on speed and strength and work to post an even better time. If he has a nice bat and arm, 7.0 will not keep him out of college baseball. Some D1 coaches consider 7.0 a minimum qualifier outside of positions such as catcher and 1B. If he can hit, he can play at 7.0. It may not be in centerfield, but he can play somewhere (e.g., RF, LF, etc.). The idea for hitters is to be in the lineup somewhere. I wouldn't worry about the position so much. PG posted a great article here about improving 60 time. Use the search engine feature here to find it.