Change DTIM settings?

[RicN]

I have some questions on the DTIM period setting, available on the Procurve Access Points and WES module.

1. Does the wireless stations have to be configured/have support for the very short sleeping periods you get from DTIM?

2. For a laptop going on batteries, is there any noticable gain in battery lifetime by using DTIM at all?

3. Do you ever change the DTIM period to longer/shorter? I am thinking if question 2 is yes, then would it be of value to raise to DTIM period to 3 or 4 perhaps?

If you have any answer or good guess on any of the question I would be very grateful!