In response to an earlier conversation, we're just going to have to accept the fact that Gaga will go up against Adele in 2016 and she will lose (as will everyone else). But that doesn't mean she can't have a successful era. If I recall correctly, not a single song from "The Fame Monster" went #1 and that album is considered her peak.
If she puts out good music and pairs it with good visuals, it won't matter how much Adele is slaying because that'll be enough to get people to pay attention to her.
