I'd love to hear singers talk about the demands of the role. To my ears, it's a bitch, vocally as full-throttle as much of what's out there. I saw the show twice, 9 months apart, both times Sunday matiness, and Menzel landed the role and the songs and made the theater rock. Of course, it's written in Menzel's range and with her strengths built in. But 8 times a week since November of 2013 (the National in DC) must still be a challenge. And one certainly hears, and often, how she doesn't like to appear when she can't thrill people. Many are put off by her perfectionism, but many are also put off by her failure to hit notes. Can she win? No. I suspect she doesn't show up only when she knows she cannot deliver.
"I'm a comedian, but in my spare time, things bother me." Garry Shandling