I am reminded of a past exchange with William Iorg in which he reminded me that old time bullseye shooters used roll crimps for best accuracy from the .45 ACP in the 1911. . . The taper crimp was popularized solely on the proposition that it extends case life (which it does; I've had up to 50 load out .45 ACP cases taper crimped . . .
I believe the American Rifleman once tested both the roll vs. taper crimp in .45 ACP to determine which gives the better accuracy. For the life of me, I cannot recall which one came out on top, however, loads which give a one hole group from a Ransom rest do not necessarily look the same when fired one-handed during the rapid fire stage of bullseye shooting at Camp Perry. My wobble area alone would negate any super accurate ammunition I could possiby load. My point being that we can pursue accuracy to the nth degree but at some point, other factors come into play.
The fact that you get over 50 reloads with the taper crimp in .45 ACP is, in my limited experience, phenomenal. Most of my brass gets trashed at 25 or so reloads simply due to the number of casemouth splits I have already experienced and the ones that are potentially on it's way.
As to taper crimping the .45 Colt, it's doable but why add another step in the reloading process that could result in the bullet jumping the casemouth and tying up the revolver? I believe the ammunition companies have a good reason for putting taper crimps on semi-auto ammunition and roll crimps on revolver ammunition.
