Greenmonsters
Wannabe Duck Boat Owner
The reason the higher levels have F2 back up 1st is that they only have to play 1 game per day. That will not wear out their catcher.
This is true of HS games too, but unless a TB team only has 1 catcher, they should be in good enough shape so that backing up first base isn't going to be the straw that breaks the camel's back.
IMO, catchers should be taught to back up 1B when there are no runners on so that it becomes instinctive. If its unbearably hot or they've got to catch consecutive games, then you can give them the OK to not do it; however, don't be surprised if they continue to do it as it becomes a matter of pride unless you expressly prohibit it. One of the intangible benefits is that it may help motivate her teammates to always hustle and think twice before complaining about how hot they are!
GM
GM