What I'm saying is that while 6-7 might lose out on edge due to the cap, maybe they weren't going to gain any edge anyway, either. And they still have 6-7 edge if they didn't earn any. Likewise, just as 5 edge can gain 2 edge then "start" at 7, maybe they won't be gaining that 2 edge and be at 5 anyway.
Illustrated: PC A has 7 edge. PC B has 5 edge. Since they're a team, they won't be fighting each other but some other number of NPC(s).
case 1: PC A goes first. PC B cannot gain 2 edge during the course of PC A's action. Granted, PC A can't take an edge point anyway, but if PC A were at 6 or if PC A had already spent some edge, PC B could give some edge away.. but then he'd be even lower than 5 for when his action comes.
case 2: PC B goes first. In the event PC B does not gain edge, PC B is not at the ceiling. Furthermore, PC A has the opportunity to spend some edge to give away to PC B, who can then be in what you're saying is the more enviable position of sitting on a slight deficiency for HIS action when it comes up.