Long ago - in the days of points ignition - I would set the dwell for good ignition at WOT/redline and feel the coil at idle to make sure it didn't get too hot.... not very scientific, but it was all I knew to do. With today's stuff, the dwell is constant, so we don't know what the coil really needs without doing the calculation in the MS manual.... or trial and error for a best guess "feel" as you have done.

What started me down this road was the initial attempts to start the engine on the range 7 plugs and I said the plugs read like weak ignition. When it ran on range 5 & 6(but not on 7), I became more curious - and even more so when I swapped in the Diamante coil with a slightly lower secondary resistance and sensed a slight difference in ignition quality.

I guess that even knowing what the dwell "should" be will still leave room for "feel", but it seems to make sense to know where the "norm" is found before playing with it. I'd like to do that before I get on the dyno, but it's probably not necessary.

Generation One sent this webpage - you might find the coil information useful:

picotech

Frank