Good points. With that in mind I think it would be better say, that it's the degree of suspicion that should justify the lenghts to go to, to confirm that you are dreaming.
I don't know exactly when, but about 6 months ago, the need for RCs (except for FA), went away. It wasn't a complet absense of need from one night to the next, but rather a steady decline. I just started to 'know' more and more often without having to confirm. Which in itself should make you think that I can get lucid at will, but that's not the case - conditions still need to align; steady sleep schedule, the right amount of tired, WBTB etc.