Out of 200+ revolvers I've never been asked to "fill in" a hammer notch. Likewise, all the CASS shooters that I service want to "make sure" the cap post is part of the service! I've had two folks ask to not install a post, one I can't remember why but the other one was on a 2nd gen Colt that wouldn't be shot (so, no need) but he just wanted it to be set up to function the best that it could.
I just got off the phone with Kaido (yes, the bullet guy) and asked him how he likes the posts I put on his and he said he absolutely loves um!! He said he takes the pair on bear hunts and likes having six shots instead of just five.
For what it's worth, I'll be installing my frame mounted "pushrod and coil spring" (a la Ruger and Caps. Dragoon) to his and the others I have here of his.
So, as "unscientific" as it may or may not be , it appears almost all shooters desire the cap post over any other method.
Btw, The cap post is a reversible procedure as is the arbor threaded for the adjustable wedge bearing (just plug them). And of course, you could just grind the arbor to be short again and end up with the gun you started with! (A wreck !!) Don't know why anyone would want to . . . . Heck, you could put all new factory parts in it and have it possibly (probably) eat itself!
Follow me on Instagram @ goonsgunworks