I have these studio flashes by Mettle -
One of the switches on the back lets you dim the modeling light when the flash fires. I typically use this setting (ie. dim when flash fires).
I recently got an iPhone slow-motion video capturing the moment that my flashes fired. You can watch it here:
https://www.facebook.com/chrisrehbergphotography/videos/516455198687464/
There are 3 flashes in the video, but only the left two have the modeling light.
What I noticed was that after the flash fires, the modeling lights are still dimming. This says to me it's obvious that the modeling lights are still on at the time of image capture.
That being the case, what is the point of being able to dim the modeling lights at time of flash fire?
I didn't process that jumping shot, but if you're interested, here is an example of how this looks in the final shot.