If he's going to be on Skinner's line, he has to skate Skinner's shifts. How else would he do it? I mean you could swap Ryan and Wallmark back and forth on each other's line, but that's insanely hard to do in real time during a game. You basically end up giving them the physical experience of being double-shifted. At most, maybe you can make that change during the third period break -- but again, you're putting a rookie in a position where if he can't handle it, he's about to have the nightmarish experience of being blamed for a key NHL loss 24 hours after being called up from the bus leagues.