>I thought 6.0 SP3 was a HUGE breakthrough because it allowed compilation on the fly.

See? Everyone has a different take on what constitutes a break-through. :-)

>This only applies to COM/ActiveX objects, yes?

Yes.

> Or can IMPLEMENTS be used with native Fox objects (in other words giving Fox classes pseudo-multiple-inheritance)?

IMPLEMENTS cannot be used in that manner, and I'd argue that you wouldn't want to anyway. Multiple inheritance: yuck.