That may have been me you were referring to. If someone's injury is for "1 week" that can be anywhere between 1-13 days. So you can only safely set your line up on the day of, and after the injury is over (games 14 days from that point).
You need at least 3 (3 or more) to not forfeit then business as usual. There technically is no "weekly max" unless you set a personal one. The only negative impact I can see is 48 mins = more chance of an injury in the game. So less minutes played is less chance of injury. If you don't need all 48 minutes, just getting $1 subs to get "just enough" minutes would be the safest route to take (that I can see)