In song record, you can select the recording track to multi. But it doesn’t do anything different as far as I can see (I thought that it will record the same notes on all 16 tracks. Not that I know why someone will want that. I was hoping actually, that it will correct the problem I have when recording an arpeggio, that only part of the arpeggio notes are recoreded).
What is the proper use of the multi feature?

Re: multi track

What is the proper use of the multi feature?

The proper use of the MULTI Track Record feature is that it puts all 16 tracks in record. Since you can only play on 1 MIDI channel at a time, obviously it is not for you performing on the keyboard. Its use is for when you are transferring data from another sequencer into the Motif sequencer. It will record all 16 MIDI channels simultaneously and each MIDI channel will go to the correspondingly numbered track.

Hope that helps.