DEQ2496 RTA and Microphone Techniques

As mentioned in other threads, I enjoy using a Behringer DEQ2496 to switch between HDTV and PC inputs on my desktop.

There has been some discussion of the RTA process in other threads, but can anyone comment on how critical it is to place the microphone correctly?

Is it OK to put the microphone on my desktop between my speakers, or is it critical to position it as if it were between my ears when I am in my usual working and therefore listening position.

Microphone pointed up or at the speakers?

I find I usually consider the RTA to be a rough curve, and then smooth it out a bit more by hand.

Any other hints or techniques greatly appreciated.