Chris, I wouldn't worry too much about it being behind the TV then - I've done a few deployments with Aruba's equivalent of these APs, and in such a small space to cover, the TV is not a significant factor (most TVs have an aluminum backplate to the ...
As long as you account for the attenuation in your design and have a modicum of airflow around it there shouldn't be an issue, I have placed some behind bookcases and behind TVs without significant ill effects. In most use cases for these type of APs...
That's going to be problematic for anyone below the base of the AP. Imagine the coverage as roughly a hemisphere. This is basically omni on the front, and little to no coverage to the rear. You *could* put it on a ceiling and get decent results.
