Well. They can do that if they want. Tony said his next two albums would be with Gaga. She could easily do a "pop" or whatever genre she wants, then jazz, then go back to her "normal" genre, and go jazz again. I have no problem with that, as long as she's happy.
Gorl, no. Cheek to Cheek was cute but I only used it for a little while. They're a cute pair but I can't do two more Jazz albums. Either give me ORIGINAL jazz songs, or try to get Tony transitioning into a new genre just like Gaga did herself.