Never experienced the roosting scenario you described ... but feeding, my experience ... not in the least. While deer and turkey are definitely curious about one another, I have seen them compete over available acorns. I never seen one spook the other in any fashion or form as long as both were not in alarm mode. In fact other than having more (and great) eyes in the area, I think that when deer see calmly feeding turkeys, they settle down as well.