I get your point about needing to check your sources after calibrating the TV. I think a video generator is overkill. Blu ray can be tested with the free AVSHD disc, and trying to calibrate the tv signal is a fools errand, imo.
I agree, that autocal does not provide perfect results. From what I've seen on other people's system, it's a good way to get close, and then requires manual tweeking.