I'm just thinking out loud really, but I've noticed that in grouped sessions (or at Dolmens or World Boss sites) most MOBS simply die a death in a broiling mass of spell energy; the fact that I and others are stood in the middle of it all, unharmed and dealing hand to hand damage feels kind of odd.
Now of course it's fine the way it is and ESO is designed and balanced that way so that the appropriate MOBs are tough enough to be trouble whilst taking that sort of damage, but it does foster an "unload all you've got" approach to group combat.
I can't help thinking that that friendly fire might offer a interesting and slightly more cerebral approach to grouped combat (as long as the MOBs were balance accordingly). It might be particularly interesting in Cyrodill which has a more medieval battlefield feel about it - softening up the enemy with missile combat (or taking out the enemy's artillery) before launching a ground offensive and talking to the rest of the team before charging in case they take you out as well.
Of course ESO isn't a strategic war game and I love it the way it is, but I thought that it might be an interesting point for discussion.
I am one of The Great Mediocracy, those whose role in life is to provide the baseline by which The Few deem themselves Great.