The Vampire is basically an enhanced 060 with full 020 (the most complex of them all) compatibility.
What grond tries to say here, is that the Apollo Core 68080, which is the CPU used on the Vampire, is basically an enhanced 060 that is compatible with software written for 020 (the most complex of them all).
Compatibility is important, compatibility between software and hardware - not between two pieces of hardware that will never run together :p
And really - 68020 is the most complex 68k?
