I dont think that there would be any benefit... but you would certainly complicate your brew day
Instead of mashing different grains at different temps... balance the body/fermentability by adusting temp. I mean, you can mash anywhere between 145F and 158F to vary the fermentability and body of any beer.
Instead of mashing at 150F, try 153 for slightly more body/less fermentable wort. Instead of mashing at 158F, try 154F or 155F for a slightly dryer/more fermentable wort.