So if D* has your locals in HD there is no advantage to having an OTA module or ability.
Not true. Having the AM21 ota tuner allows you to record channels that Directv doesn't carry. Here in the Hartford market, one of the locals isn't carried by Directv in hd. Also, there are subchannels available in many areas that Directv doesn't carry that are ota. Unfortunately, not all of these are in the database of the AM21, a real drawback to the way that Directv programed the AM21.