MS1 only... "hold ignition" I suspect is like "skip pulses" on the later code, to give the engine a few crank wheel teeth worth delay when cranking before firing off.
MS2e/3 only allows 10 teeth max anyway, if anything I'd prefer to crank much longer just to get oil pressure first.
I don't think it can do anything in EDIS mode, as there is no spark cut or on/off capability, MS can only control the EDIS subsystems timing. Zero makes sense there, but it probably doesn't matter.
You can pull the MS ecu out and the EDIS will still fire at 10BTDC as long as its powered up and you are cranking.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
Just trying to get things squared away on the software side of things as I had a mare of a time reading the timing with timing lights, think I got it the same but still a tad doubtful! Can't give my 2110 more then 26 degrees at wot without pinging....