I do basically the same as you do for both chicken and turkey but you just managed to describe it much better than I :)
I feel that taking each breast side off in one large chunk keeps it moister for storage. Plus it’s easier to get even slices of the white meat and with each one having approx. The same amount of the delicious skin.
When people just start at the top and slice downward then the first cut from each side of the breast has the lion’s share of the skin. Not fair.
Plus, I think that the white meat left on the carcass tends to dry out much more quickly because of the greater surface area which is left exposed.