There was a discussion on the ALR forum a while back regarding rifles with no buttplate. At least a couple of the professional builders over there commented that most of the repairs they have done on rifle butts were on guns that had buttplates, with splits occurring mostly in the toe area. These fellows suggested that a buttplate does not give complete protection from splitting, and the screw that goes through the buttplate into the toe (more or less parallel to the grain) may actually weaken the wood and predispose it to split. A couple of photos were shown of very old rifles with intact butts but no buttplate.
I think a lot has to do with the design. A shallow crescent with a less acute angle at the toe and slight rounding of the heel, and maybe slightly chamfering the edges so there are no sharp corners, may be the key. The buttstock on Muddly's "Ginger" looks to be made this way.
Most of us are pretty careful with our guns, anyway. Like someone else who posted earlier on this thread, I bring a scrap of carpet or foam to the range to pad the rifle butt when I'm loading, and if I'm just standing there holding the gun upright, I'll rest the butt on my foot. I try to avoid putting it down on wet ground or concrete, and this is for rifles that do have buttplates. With reasonable care, I expect "Old Ginger" will be around for future generations to shoot.
I saw the post identifying James Correll as the builder. It's good to have a name to go with the gun. These handmade muzzleloaders have some real "soul" that you just don't get from the mass-produced guns, and it's good to know a little about their "pedigree." I had not heard of James Correll before, but he sure did a good job on this rifle. That will be a name to watch for.
Notchy Bob