* When you think of - and refer to - a failed reality check, what is it that you are thinking of most often?
For me, it would be the first scenario that you described.
*In what ways do your RCs fail you?
I always use the nose check. It's only ever failed me once - I couldn't breathe through it. However, I was fairly certain at the time that I was dreaming, so I checked my hands after that and found that I was indeed dreaming.
* In what ways do you rationalise away RCs that yield dream-like results but that don't trigger lucidity?
Actually, as far as I can recall, I have never done this. Which is not to say that I've never been
tempted to do this - like you said, sometimes I will suspect that I wasn't pinching my nose "tight enough." In the end, however, I will be firm with myself and just say, "look, this may not
seem like a dream, but I know that it's
impossible for me to breathe through my nose when I have it pinched tightly shut, so this means that I
am definitely dreaming. Then once I start flying the doubt usually leaves my mind

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