Motorbike: Least worst option for stuck front sprocket bolt?

Had a particularly stubborn front sprocket nut the other day, wouldn’t budge with the rear brake – breaker bar combination.

Tried giving it 5min of blowtorch heat, didn’t help.

Then, even with my pal putting his full weight on the rear brake pedal (some brake fluid even leaked out at the rear banjo bolt), the rear wheel would still eventually move. Put the motorcycle on the ground, same thing, wheel would slip on pavement.

Finally, solved it by putting the transmission into 1st (obviously a poor idea).

This got me thinking: assuming all else fails (impact wrench, etc) how bad is it to put this much torque through the transmission? Doesn’t clutchless shifting at high speeds put at least as much torque into it?
Is it a ‘not even once’, or more of a ‘don’t do it too often’ kinda deal?

The alternatives were not too great either: putting a bar to jam the wheel/swingarm could deform the wheel, and some say that blowtorching the axle/nut is a no-no.

What do you guys think?