It kills me how obvious it is that whoever thought it was a good idea to drop the V that far had no substantial personal experience with breasts. It was clearly someone who thinks breasts are hard, solid, fixed masses that wouldn't, oh, get pulled down by gravity when you wander around obviously not wearing a goddamn bra, or get slingshot around and fall out of your "shirt" when you are maybe doing aerobic activity like fighting. And since whatever the hell is attached to her chest is very clearly not breasts, she now looks miles less sexy than she did when she was wearing the halter, because my subconscious is too busy going "WTF" to register anything else.
Maybe we can trade the "cleavage" in and get high-heeled boots instead? They'd be a lot more palatable on Donna, who can just fly wherever she wants anyway.