Just to be sure... Adjusting the Pool Threads should increase the performance on the IIS server?
And it's recommended to set it to twice the amount of devices.
It is not there by default, so you have to create it. The default is 2 x MB of RAM eg. 4GB =
PoolThreadLimit = 8000. So I should not change this setting, right? Unless I manage over 4000 devices?

One more thing; from what I can see in the IIS docs the limit is 256, is this true? Because another site says
"Range: 0 - 4,294,967,295 (unlimited)"
So if the first one is true is should give nothing to set this reg key. A bit confused right now... ;-)
I guess it's the last one that's the right one.

So maybe this is the case: it's used as some kind of limit to make sure ZMM does not kill the IIS?