MEL ops procedures do not apply when airborne.
.. but the wise pilot will use the MEL as a guide to those matters which might be important to think about.
I agree. It will inform you if the next sector is a go or no go but do not fall in the trap of wanting to fly at all cost to an airport with adequate maintenance to avoid grounding the plane. You may not want to stay airborne for that long.
MEL is basically a recertification (CRS being signed off) and therefore does take into account the effect of an engine failure. With this in mind certain requirements that seem unlogical at first suddenly become more obvious.
It's useful to carry a blank loadsheet in your flightcase.
but, for the fuel scenario, not much use unless you understand the design of the sheet and how to modify the use to account for the non standard fuel scheduling
Part of the type rating course in any company that respects itself.