Matt what is that internal delay?
The electronics take time to process. The more decisions it makes internally, the longer it takes. Normally no one notices. But on an engine spinning 5 or 6000 rpm or faster, that time can equal a degree, or two, or three.
"For some perspective do the math:
6000RPM / 60 = 100 revolutions per second X 360 degrees = 36,000 degrees per second.
Each degree is 1/36,000th of a second or .00002778 sec." from Spark Lead (you may have to join speedtalk to see this thread)
More in these speedtalk threads, which don't require joining: HEI - Retarding, Slew Timing Light inductive delay
The only down side to dial back timing lights like that is that they don't like multi strike ignitions. They can throw multiple flashes making it all but impossible to set timing on multi strikes. ...
I bought MSD's light because I was concerned about that problem. The Innova seems to be OK with my MSD 6T. I also have a Craftsman inductive and should compare. But current engine doesn't have a timing tape on it, so thats a ways off.
But when I was looking for the speedtalk posts on slew, there was also this one about problems with an MSD. http://speedtalk.com/forum/viewtopic.php?f=1&t=33249