@LuketheSmugger
Normally I would agree with you.
But considering the opponent is so eager to get them to stop might suggest he has his limits too how long he can keep it up.
It might be that he requires a lot of energy to block every attack, and is afraid that he might run out of magic.
Not to mention, its the only thing you can do if you don´t have access to any none physical attacks anyway.
Granted the fact they combined as they did would suggest they have some magical skills... but still...