Steve -
In the sixties I was half owner of a Cessna 210, I took care of any paint repairs that were needed, mostly paint chips from takeoff and landings with particles on the runway hitting the finish. While learning and using the paint application I saw the reference to induction, as a supplement about the paint system. The paint was DuPont Imron, a polyurethane system.
The difference induction made was subtle, but decidedly effective. Sprayed over a larger area, I could see that the paint layed on smoother and settled right down. With polyurethane paint applied to an aircraft there is no "adjusting" mixing amounts, the activator is a critical element and is to be measured accurately.
Same with model painting for me, I see a more predictably good paint layer being applied when I do my mixing, then waiting for those few minutes before actually laying the spray on.
I'll say it's even more noticeable when using straight enamel, although I have completely abandoned that from my inventory. Just how much someone else might notice it is questionable, but I use the method and am happy to continue as I do find it beneficial.
If I had to guess what induction literally means relative to paint solutions, perhaps it's an opportunity for the mixed ingredients to chemically blend more completely. But that's just a SWAG on my part, cuz I ain't no danged expert.
Glad you like using your new Mr. Color system, and by the way I have been using Leveling thinner for a while now, but rely mostly on IPA or X20-A. Even though I have an effective spray booth and fan/filter setup, the El Stinko factor of Leveling Thinner is rather obnoxious while mixing.
Patrick