[Loopy]

Without summoner:

28 Demonologists summon 26 Cerberus (Cerberi?), 26x90 = 2340 leadership, talent says 1470-2940 so its correct.
3 rune mages with maxed magic runes summon 60 Angelic Guard, 60x60 = 3600 leadership just as talent says.
16 Engineers summon 16 Guard droids, 16x120= 1920 leadership, talent says 1600-1920 so its correct.

With summoner it is all the same except demonologists summon around 4.5k of units, which is actually slightly higher than they should but I suppose the game rounds up. Yes, I made sure that I had enough mind runes after buying 3 ranks of summoner so the rune mage's power didn't go down.

Perhaps it was a patch change? Rune Mages seem overpowered as it is. If summoner were to affect them then they would be able to summon the Phantom Gyphons with about 90% physical resistance after all my + items and they would be making about 7.2k leadership worth of them even as my personal leadership is only 6k. All that would be ludacrisly overpowered, without summoner its only about 4.8k worth of summons which is at least a sane number even if it is still really strong. As the person who just started playing this week, I hate to call you guys wrong, but maybe you should re-test on your own game to see if it still works? I'm at patch level 1.3.1, tell me if you are using a different patch. As I said before, going by a strict reading of the skill it makes some sense. Rune Mages don't summon units, they create them, so it shouldn't affect them. It might have even been a bug before.