A split brass on a larger locomotive works best as a "re-usable brass" not and "adjustable brass". You machine the brass to the size of the pin and run it until it is worn, Take the brass out, cut it through the pin diameter, Mill enough out of it make it the correct size again, put it back together and run it. The wedge always stays tight, and there is no adjustment to be made on the road, so the road crews don't have anything to tinker with. 463 has split brasses and that was how we ran it.

The big advantage of the later style rod is it allows for a "floating" bushing on the main rod. In this case the brass wears both on the pin and on an insert pressed into the rod and the brass is free to turn within the rod and around the pin. With this arrangement, you get twice the mileage on the brass (it not more) because the wear is on both sides of the brass, and the brass can turn making it wear more evenly, whereas the old "split brass" wears at each end mostly, and not as much in center.