I hear exactly what you're a saying, Kees.
I recall over on ALR Larry would time not only flintlock ignition - but caplock as well.... If I recall his findings correctly,,, they both were fast and there was not enough difference between the two to really even make a difference... However, many a mind set is still that there is a difference they can personally register.
I feel this "thought" process of difference is only in the flint hitting the frizzen, and nothing more. Mentally for many - they just can't shift their focus away from wanting to watch and see if the pan powder ignites when they pull the trigger on their flintlock. No doubt I was the same way 40+ years ago.
I've shot both cap and flint long enough now that it doesn't matter to me which one I'm shooting - but I'll admit that I get better scores from my caplock rifles, even though I don't believe I flinch with the flintlock.
Speaking of flintlock rifles; I took my new build out to the Range this morning (wanted to get use to the feel of it without wind) so I set a 10 inch gong up at 50 yards - then walked out to it and from 25 yards I took 2 shots (hit it both times) and moved back to 30 yards and hit both shots from there - moved back to 35, 40, 45, and 50 and took two shots each time from each distance and the only shot I missed was my first shot from 50 yards. All shooting was offhand. No wind sure makes a difference. Thing is, I knew I missed that shot from 50 yards as soon as I pulled the trigger. But,,, the rifle's getting broke in to where I know it and feel comfortable with it. It was a fun morning.