It won't sound like leftovers, Taylor sells more than Katy now so she will get preferential treatment. Katy's next album is going to be a mess though! Dr. Luke won't forgive three of his hits going to waste.
But Katy is still the cash cow and until now was guaranteed success. Taylor sells albums, but only has a few pop hits. She is the bigger risk. Plus 1989 was made after Prism and I guarantee they are going try follow the Teenage Dream formula with Taylor. Shake it Off is also very Katy-esque, but even more childish.
Baby, if you loved me, you would call me your bunny
Tell me that I'm just a baby, honey
Beat me and tell me no one will love me
Better than you do
Better than you do
The Ultraviolence that's better than the real one.
1. Those were promo singles and neither were sent to Pop radio. Neither got actual promotion besides a Grammys medley w/ FLAB.
2. CIL and Foolish were not record breaking singles on radio nor were they in the last 10 years.
1. FLAB was sent to Urban Radio and Say Somethin was sent to Pop/Top 40; it even charted. Lack of promo or not, they were still singles that flopped. The same can be said about "Birthday" which had no promo besides a pre-recorded performance.
2. Foolish was a record breaking single (Most weeks for a debut single by a female and something about sales). But since you're talking about Last 10 years; Black Eyes Peas have that on lock with The END era.