While it is possible to use the both eyes open Bidon (sp?) Aiming Concept with the ACOG, I have found it much harder to use, even with practice than the red dot sights. The way it works is you use both eyes open, and focus on the target with your non dominant eye (eye that isnt looking through the scope). The red chevron (or triangle or donut) will superimpose on your left eye's image. This gives a red dot scope effect. The problem is, you will naturally look through your dominant eye first, and there you are greeted with a zoomed in blurry image. Practice can overcome it I'm sure, but I'd stick with the red dot for CQB.
Don't get me wrong, I LOVE my TA31F, just not for cqb.
As for "most SWAT hate the ACOG"...having worked with members of a SWAT team for the past six months (I am not an officer by the way) I can tell you that they don't "hate" it. As a matter of fact many love it. It all just depends on WHAT you need an optic for. The ACOG is NOT the best scope for close up, and should not be considered so. If you need an accurate, fast shot at 100+ yds, it does great.