ABC insiders say Katie Couric‘s post-Super Bowl appearance on “Glee” may have been trumped by Diane Sawyer‘s faux feud with Sue Sylvester, played by Jane Lynch. Sue ended Couric’s appearance with, “I hate you Diane Sawyer.” Sawyer closed “World News” the following day with, “Watch out, Sue Sylvester. Watch out,” and tweeted: “It’s on. As a [former] rejected Seneca JV wanna-be cheerleader I’ll meet you in the gym — bring the cannon.” Sue responded on Twitter: “Bring it on, Diane Sawyer. Your next gig will be hosting ‘Good Morning Emergency Room.’ ” Now “Glee” star Matthew Morrison has donned a “Team Diane” T-shirt and invited her on the show. An ABC insider sniffed, “Katie did the show, but Diane is getting all of the attention.” “There’s enough ‘Glee’ to go around. We loved Katie’s appearance and this is only about having a little fun with the irresistible Sue Sylvester,” said ABC rep Jeffrey Schneider. Couric’s rep, Matthew Hiltzik, responded, “Seriously?”