I know little about trout but those who can address your questions will be along shortly.
I do have an observation though in that rainbow trout seem to be sensitive to being caught. One of my friends has a place on Colorado's White River. He had the pond stocked with trophy rainbow trout, and, on a visit there, gave us permission for catch and release fishing. We caught two and released both. In the crystal clear water, both of those huge beautiful trout sank to the bottom and died. Of course, that ended the fishing, but I have been bothered by it since, and still don't know if there was anything we could have done to avoid the deaths of those fish.