re: Legally Blonde.....
I think the problem was that the cast of Big River dispersed after the show closed. To summon them all back to perform on the Tony telecast would've been expensive. Showing a brief video of the lauded (but shuttered) revival was more than enough. Meanwhile, I agree that Blonde will not be performing. They're not nominated for Best Musical. Finally, do they really need a performace? It's such a recognizable commodity anyway. People will flock to it when they hear that it exists.