> So, I'm not sure where the "internally clock-doubled" notion comes from :-)

It comes from the fact that the 68K family has always (well, 030 and up I'm
sure) operated the processor clock (PCLK) from twice the bus clock (BCLK),
I think by simply clocking with both edges of BCLK.  Once Intel's hype made
people forget that their clock-doubling gimmick was an apology for inadequate
motherboard designs and thus "clock-doubled" became a positive marketing
buzzword, Motorola types started using the phrase to cover the PCLK/BCLK
relationship, even though there's no PLL synthesizing PCLK from BCLK.