Anything that promotes and compliments an auxilliary cooler is beneficial for hydraulic transmission fluid.
The optimum temperature for hydraulic fluid is 120 F. Temps above this value are detrimental to the long term health. Replacing fluid often is one solution.
Most of our trani'* run about the same temp as our engine coolant. This is too high IMO.
The GM designers have many other considerations they have to consider that are no always good for wringing more HP from a drivetrain.
I may seriously consider this mod.