Can anybody tell me if the actual wheel can be separated from the center gear assembly without damaging it? And if so -how?

You mean actually remove the wheel from it's cradle?

Not sure if this has been done or in fact what the point of doing it would be.

These maybe useful

LINK ERROR.y=193392314111966814

Thanks for the link, I read the thread before.

The point would be to be able to fix the steel wheel to a drill and grind it down until it's a snug fit for the gear ring, while keeping it perfectly round. I guesstimate the radius would be around 0.4 mm smaller then, so probably no problems with the connecting gears.

This of course to avoid adding extra teeth, which always seems to be flimsy and very hard to get aligned perfectly...

Hmmm, that would work in theory but you've still got the problem of the progressing shrinkage.  But you're right, the reduction in diameter is minimlal, so yeah, a nice idea.  I'm going to have a look at one and see if it's possible to remove but I have a feeling it's supplied as all one piece because it's made as one piece.

You can separate it, from the lever, you need a thin blade to pop out the metal ring that hold it in place. It's just pressure in, can be put back. I thought about grinding the metal disc down, the only thing I worry about is wow and flutter, if it's not perfectly round, or gears not catch due to it's to small.

Trust the dentist (me) always better to give the thing a few new 'false teeth' ...easier,faster,safer & effective

a) you wouldn't want to snap the plastic outer into two bits and

b) yes ...perfect circumferential grinding could be tricky on two counts (i)uneven grinding (ii) accidentally making the gear wheel end up a teeny weeny bit smaller