I must be. I am!! Thank you!
But I've never been "recoil sensitive". I would imagine that among the troops there were many who would not be bothered shooting the rifle load in the carbine, who were perhaps "gun guys" to begin with and then there were many "city boys", new recruits, not experienced with firearms, or more recoil sensitive types who were bothered by it. The solution of course would be the lighter load to improve marksmanship with the recruits and those who were more recoil sensitive. ? That's my theory, and I'm sticking to it! I really don't think the rifle load kicks that badly in the carbine. And I don't think
every trooper would have found it "objectionable".
The 55 grain carbine load did have it's disadvantages, the rifle load, from the rifle out-ranged it quite a bit. At the battle of the Rosebud, when the Cavalry troops were getting hard pressed, or in a pinch, they would then have the infantry come up and put more effective rifle fire on the enemy, and drive them back.