> But it cannot *write* at anything other than the normal speed. Hence copy protection
> taking advantage of this was a good choice.

You can vary the speed enough to write Mac disks by playing around with an extenal clock on the genlock port. There was an adaptor back in the day which did this, it screwed up the display when it was writing though :-)

I was going to buy one, but never got round to it.

smf