A: No and yes (or vise versa). The HD recorders will never sync to incoming MTC or MIDI Clock + SPP, but you can create a situation in which you can control most common transport commands of the HD recorders from out your sequencer, provided your sequencer can handle MIDI Machine Control. You will need to connect both MIDI In from the sequencer to the MIDI Out of the HD recorder and the MIDI Out of the sequencer to the MIDI In of the HD recorder, because the sequencer will send, for example, a Play command to the DR-4/8/16 and the HD recorder will subsequently react on that by sending MTC or MIDI Clock (or whatever timecode it is able to generate simultaneously) back to the sequencer, making the sequencer follow the requested operation. In most cases even individual Track Arming can be done from the sequencer. This actually give the fell of the recorder being slaved to the sequencer although, in reality, the recorder is the source of the timecode.