Custom pistolsmiths respond to the demands of the shooting sport or the practical needs of their customers. Sometimes the modification makes sense and others times it doesn't. An example of the former is the speed bump at the bottom of the M1911 grip safety. If you use today's high hold with two hands, the base of the shooting hand thumb will sometimes fail to fully compress the grip safety. A larger pad of material just ensures that the needed contact is there, and that's a good thing. But a revolver trigger guard cut away at the front is at best a modification that makes sense only in the hands of the most experienced handgunners on the planet. For most of us, it's a bad thing.
Here's an idea that might make sense on some of today's hot shot revolvers, which are invariably fired single-action. King Gunsight Co. used to build what they called the “Cockeyed Hammer.” It was a standard hammer with additional material welded to one side of the spur—the left side for a right-handed shooter. The extra material was then shaped and checkered to form an off-center spur. I have them on a couple of guns, and they really help with speed cocking the revolver for such events as the Rapid Fire matches in which the shooter must fire five rounds in 10 seconds.