Some good options.
Like i said, everyone feels different.. What works for you, may not work for me, and vice versa. If this guy has been doing rear delt isolation work, maybe it is time to switch it up, and hit **** heavy.
You re a power lifter, you already went down that path, and you needed to go the other way with your training. Makes sense.
But let me ask this.. What is your bodyfat? You would be surprised at how many people think they have no rear delt development, or under-developed rear delts, because their BF is higher, but when they diet down a bit, what do ya know..rear delts..lol
Not saying this is the case with you, but i have seen it.