What would radio's reason be for shunning Gaga? Not arguing that they aren't, but I wonder what the reason could be. Has she just gone too long without an actual hit? Radio can be fickle. Few missteps and it's hard to get back in good graces. She's definitely racked up the hits, but it was in a concentrated period at the start of her career.
Sales wise she's basically Xtina - each album selling less than half of the one before.