Klaine in season six got some of the worst writing any TV couple has had ever. Ross and Rachel bad. Some of it is Ryan Murphy pissing on the fans, which is high level bullshit given how much we've put up with from him. But I think a lot of it is that after Cory's death they didn't have any other couples they could give drama to, so Blaine and Kurt got a double dose. And in season six, they couldn't do anything to Brittana because they wanted to please the fans, so Klaine got 3x the conflict.