Your grandfather was awesome. No question, full stop. Slightly insane, of course - how many screws do you have to have loose to charge into combat armed with a medi-kit?
I know two classes of magnificent lunatics. Pilots and medics. They are both nuts. Though you might add a third - chaplains. I distinctly recall one taking a weapon once and saying “No” in the sort of voice that makes you run like hell. Totally flat. I was sort of floating in and out, but it scared the crap out of me. Sounded like a demon talking. Might have been the drugs, but damn. It was scary.
My mother’s dad died when I was 31 so I got to talk to him about WW1. He was really a quiet and mild- mannered type and struck me as one who would not be phased much by the shellfire, noise and chaos of the Front. He did tell me that what bothered him most was trying to figure out which wounded troops to spend time on when there were too many....fairly lightly injured; ones hurt so bad you didn’t think they could make it so he would give them morphine and leave them and then the ones in between who were in bad shape but savable. Making that kind of decision under pressure is pretty hard.
I have his WW1 discharge in a nice leather tri-fold and a set of his dogtags on a piece of green shoelace. They really do look like dogtags.
Don’t know what happened to my other grandfather’s stuff.