the problem with sighting in at 20-25-30 is all three pins will basicaly be touching if your using horizontal pins, I like a window in between and use that window for in between shots.
I was taking into consideration his shoulder injury and assumed he would not be pulling much weight that translates into slower arrow speeds.
20 - 30 yard gap would be pretty large. Thats why I suggested 20 - 25 -30 yard pins. Gap shooting takes a little while to learn correctly. To close to the season IMO to get gaps down pat.