Slightly offtopic, since I've never actually booked an accessible room, but about ten years back, I broke my left leg pretty severely. ( I still have a rod, two plates and about a dozen screws keeping things ship-shape in that leg.) I had just given up my knee scooter before our Amtrak trip and was using a walker and cane to get around, but I decided for convenience sake to leave the walker at home and rent one at our destination. My husband and I were in a bedroom, which I managed to hobble to pulling myself up the railings, but the SCA saw me having trouble and asked if we'd prefer the accessible room, which hadn't been booked. He went off to confer with someone about whether this was possible, and came back saying that it was. He moved all our stuff, and half-carried me piggie back style down the spiral staircase! That guy earned his tip and then some!
So, if you have a disability that you think wouldn't necessarily qualify for the accessible room, I recommend checking on its availability before you travel. It really made that trip a lot easier than it otherwise would have been for us.