You're correct about this. My last duty pistol was a Sig P226. We trained so much with them, that I had to really keep up with training on my personal carry Glocks as well to remain accurate. The difference is significant.
Going back and forth is what really got to me. That was the main reason I consolidated in about 1994. It has also made me hesitant about moving from an 870 to a Benelli or trying FN SCAR. I’m supposed to go pick up a SCAR 16s in a few weeks to try out for a month of so. I’ve had my eyes on a 17S for some time.