Yes = dwell angle is still a factor in transistorized ignitions. It is = no longer adjustable but through software it is possible in distributorless ignitions, but no the service tech cannot do so.

Dwell is expressed in degrees of distributor shaft rotation. = 30*dwell on an eight cylinder engine would leave 120* of cumulative rotation for the coil to be off charge and therefore = cooling somewhat. 45* on a four cylinder engine would leave 180* to = cool, and 180* to charge the coil cumulatively. Simply because the = distributor shaft rotates 360* of course. If you have a transistorized = ignition, breakerless whatever, you can still measure the dwell angle. = If the system is weak chances are you will find a shorter dwell = angle when you test it. I have done this and I know it works. In = fact, transistorized ignitions can and do have variable dwell periods = factored into the circuitry on some applications. In reality the hall = effect sensor is simply a switch and not the conductor that all current = must pass to charge the coil and this leaves you many possibilities.

= To understand this best it is best to realize that dwell exists even in = distributorless ignitions, though it is often ignored, it is a = percentage of time in a given engine revolution. That doesn't matter = but that it is important to realize that without contact points you = do still have a dwell angle.