Canon's original intent with the 85mm f1.2L was to make it a manual focus lens, similar to its reasoning for the TS-E PC lenses (although at the time of design these presented their own problems, before Canon came out with another set with AF instead of MF). During its testing phase it was paired with the early EOS 1 and later 1N, and it performed the task well but not quickly. This was never the camera's fault (remembering how fast a 1, 1N or 1V can focus a f2.8 400mm tele...). Like several MF lenses that have a long focus throw, even the most powerful micromotors are not efficient enough, even now, to move such large elements and mechanics with speed and precision. So the final lens was never released as a manual focus but AF with critical design was concentrated on optical performance and this is where the lens excels, and it is also a small price indeed to pay for its notably slower performance.
The 85mm 1.2L was written up in the Canon Lenswork more than a decade ago. I'm wondering if there has been any further incarnations beyond the 1.2L II. I haven't seen any.
