CCamfield said:
I'm not speaking from experience here, but if everyone has an equal number of cohorts (of course, that may not be the case) then having one character get taken out seems pretty parallel to having one character taken out in a party without any cohorts: one quarter of that party is gone.
Speaking from experience, taking 1/4 of a 12 character group out is not like taking 1/2 of a 4 character group. Why? Because you get greater imbalances on on a smaller scale.
What the heck do I mean by that?
Let's pretend that you have 4 red knights and 4 black knights. The two sides fight with each red knight fighting a different black knight. It is a balanced fight. Suddenly, one of the red knights disappear. The black knight that was fighting him can suddenly turn on another red knight creating a 2 on 1 advantage.
Let's pretend that you have 12 red knights and 12 black knights. The two sides fight with each red knight fighting a different black knight. It is a balanced fight. Suddenly, three of the red knights disappear. The 3 black knights that were fighting them can suddenly turn on one red knight creating a 4 on 1 advantage.
This is a rather simple example, but the same theory applies to lots of actual scenarios: an equal percentage advantage on a larger scale creates more room for small scale imbalances.
On a separate note: Having all these cohorts makes balancing combats very difficult for the DM. He might create a battle that he thinks is balanced, but wil almost certainly result in a TPK if it gets to be too difficult. After all, it is easy to balance an encounter for a 4 PC 10th level party. It is very hard to come up with something balanced for a 4 10th level PCs, 4 8th level cohorts, 4 ECL 8 dragon cohorts and 4 ECL 8 wild animal cohorts (plus an animal companion, a paladin mount and a few familiars.)