Cutting down a steerer tube...

Just to make sure the last four pages are accurate....

Unthreaded 1 1/8 steerer is a piece if piss, right? Measure twice etc etc, bung a stem on upside down to use as a guide and get stuck in with a hacksaw, right?

I haz a question re unthreaded steerers.

If I have an unthreaded (alu) steerer with star-fangled nut already installed, and I want to cut the steerer down by no more than a couple of centimetres, do I:

a) attempt to knock the s-f nut down "just enough", and then cut the steerer
b) knock the s-f nut all the way down & out of the steerer, cut the steerer and then install a new s-f nut
c) cut the steerer and see where the s-f nut is in relation to the cut, and go from there (what could go wrong?)

I have the Park TNS-1 tool but I don't think a) is going to be very easy, since the installer is designed to stop the nut no more than 15mm below the top of the steerer. I'd have to knock it down with some other method (a punch? a bolt?). Do I just knock the existing nut down far enough that it's out of the way, and then cut the steerer and install a fresh nut? Will I feel the extra weight of this redundant nut on the commute?