What's the logic here? Is playing doubles really close enough to singles that it'll give him a hit without risking injury?
I thought the shotmaking and so forth would be so different that it would only be useful as a workout. Then again, maybe it's more of a mental thing.
Doubles is completely different from singles, it's pretty much serve and net play. It demands way less physically.
Maybe it's the point, he's just not fit enough to play singles yet.