Okay here goes.
We had an experience where a person got fit for a driver. They loved a certain brand and were fit to another. The results were not close. I mean 20 yards of difference and dispersion 100% better. Yet every 3 holes they would grab the other club and kept blasting them out of bounds. The fit worked. It didnt hurt that their brand and club head was a turd, but it was hysterical. Two days after event, went right back to old driver and said it was feel. All good by me.