Interesting,
Thank you John and Gary for your responses in particular.
So, It would require direct measurement to determine which notch the gap is quenching on. Something I can do after I am done the coil. But I could also directly measure the dwell time from that as well.
But it does not really help me right now. This is still all part of my trying to write a program to aid in MMC design. Of which the RMS current is an important factor. So I will have to rely on an estimation. I think its save to assume that we are not really going to ever go beyond 3 energy transfer periods. So one could make a good estimation on the dwell time solely based on the time for one period of total energy transfer X3. This would be the maximium theoretical it could be. Unless I am wrong on that.
At some point in the near future I will do the math and see if the time between the initial conduction set by the breakdown voltage of whatever it is in air and the the electrode moving away from the stationary electrode and the total energy transfer time x3 are at all comparable, if so then it might make a good estimation. if not then I will need to find something else.