You won't be able to rely on the conviction from merc as if they have conviction on them, you are on their screen thus a target. Minion stack or not, any random attack will hit merc first as priority and seeing how skeleton mages will be stacked ontop of you.. you'll have to be pretty close.
it might look nice on paper, but the attack of the mages is so slow that the bolts/fireballs etc are just so easy to dodge. against melee char you might have a little more potential but I doubt you can really kill a thing.
I'm not saying you are wrong, but I would like to see it work before I believe it. I mean, how do you plan on hitting something with an elemental attack that moves slower than a normal axe or a javelin. You might give them a hard time when telestomping on top of them, but the resists will most likely take care of the damage. I imagine tho, against a fireball sorc for example, 1 ball will take care of all the minions...
I don't disagree that the mages can throw out some damage. My fishy when fully pimped, has 18 or 19 mages doing about 15k per shot (total, not each) add the 85% bonus from infinity, the 70% bonus from lower resist, and you are looking at some great damage.
Unfortunately, as someone mentioned before, the projectiles are slow, the time it takes for mages to fire after tele is complete is also really slow.
I agree that damage is not the issue here, fully pimped mages can dish out some damage. But, actually hitting another PvP character with them is another thing all together.