Yes, if I believed she truly loved me for me and not because I was saving her.
No, nothing but trouble there.
If a woman obviously don't have the frame for D-cups, she really shouldn't tack them on for the Hell of it. It just comes off looking jarringly silly and unnatural.
Besides, women with more athletic builds generally tend to have other *ahem* assets which are frankly just as nice as a big chest (if not more so) anyway.