Perhaps not the best choice of words, regarding TV1 and TV2. Let me elaborate:
With the Dish ViP622 you can record two satellite programs and one OTA program, all at the same time. The OTA tuner receives digital stations, which may or may not be broadcasting in HD. It does not receive analog stations, which are about to shut down anyway (2/09). The two satellite tuners can record SD or HD. That's 3 inputs.
Separately, there are two outputs, called TV1 and TV2. TV1 is expected to usually be hooked up to an HDTV. TV2 is expected to usually be hooked up to an analog, SD only TV. You can watch a digital or HD program on TV2, but it will be downrezzed to SD.
If you wish to watch OTA on the TV hooked up to TV2, more or less live, start recording that OTA program using TV1. Then switch to whatever you want to watch on TV1. On TV2, watch the recorded OTA program. You'll be a few seconds behind, but not much. You can always watch a program recorded on the DVR while it is still recording. Many folks will start recording a program, go away, and then come back 15-20 minutes later and start watching it from the beginning (while it is still recording). This way, they can skip thru the commercials and just watch the program, and still be at the end of the program about the same time the actual real time program ends.
BTW, there is a 30 second skip ahead button on the Dish DVRs. MUCH BETTER than using fast forward to skip thru commercials. There's also a shorter (5 second?) skip back button, in case you overshoot.
You can record 3 programs at the same time, while watching 2 pre-recorded programs at the same time.
All these features (& oithers) make the ViP622 the finest DVR on the market, bar none.
Hope this helps.