I mean I can understand the outcry of summoners too. With the changes we've seen, Summoner AOE has been hammered. I too did love the absolute deletion power the summoners had in dungeons. The MASSIVE bane nerf (rip scholars seriously like what the heck) followed by a deathflare nerf (this ability was probably overpowered but god damn it is so nice) and the fact that shadowflare is now once every 60s (pray the tank gathers it inside shadowflare). We also lose out on Blizzard 2 for our AOE and Miasma 2 (to be fair, I hardly used this shitty spell). The bane nerf by itself is massive but we have to remember that we have 2 dots with a total of 80 potency per sec which can't be extended by 15 seconds anymore vs. 110 potency per sec which can be extended on live. This means bane was already going to be doing less damage to mobs in general. This is taking into account contagion's 15 second dot extension - without it, the damage is relatively the same over 30 seconds with a slight nerf but over 18 seconds, its a full 30 potency per second difference due to the length of the Bio 1 Dot.This actually does mean something because it means the adds would be at a lower HP total after 18 seconds (or 18 + 15s from contagion) than it would be with the 4.0 changes and if they died before bio had worn off, it means that the adds died faster (due to the 110 potency/s vs. 4.0's 80 potency/s)
THAT BEING SAID: Personally, I won't really care. Sure I will miss the insane summoner AOE but I was spamming BLM for dungeons before I found the power that summoners had in terms of AOE and as you said, its just a numbers game. If the nerfs are too harsh and summoners are vocal about it, I'm sure SE would do something. If people did really love the massive AOE damage and it was found that BLM's did more than SMN and significantly so, then I think those would be content playing BLM and accomplishing the same thing.... kinda ( Deathflare is too cool D: ). I was just hoping people were more vocal about the general play style of the summoner job becoming more boring than before due to its (in my opinion) oversimplification.