I will weigh in on this, as my youngest son is a corner infielder too. If your son can play both corner positions well enough to do that in college it will be a big advantage in his recruiting. The problem with most corner guys is that they don't have any measurable that is eye-popping. They don't stand out in a showcase, so their game has to be really well rounded. My kid likes to work really hard at the things he is already good at - not the areas where he needs to improve. Flexibility can be an issue for bigger guys so I suggest yoga classes or swimming to increase flexibility. That will help him improve his 60 time as well as reducing the chance of injury. Other posts are correct that college coaches feel like they can move an athlete to 1B and or 3B and therefore good HS players at those positions sometimes get recruited late in the process - or not at all. My first day of JUCO practice our coach lined all of us up and asked for each of us to state our name and position. 6 kids said SS. Only one played there. The rest of us got moved to other positions.