I wrote: > The Superdrive/FDHD does its own speed control. The controller in > recent Macs isn't capable of GCR. Roger Johnstone <rojaws@es.co.nz> writes: > That's not right. All the Macs ever made with floppy drives can do GCR > disks. I just asked one of Apple's firmware engineers. He says that late model Macs with floppy drives can read GCR, but can't write it.