Norbert definitely.
I mean I do happen to think of performance of the year when I think of star of the year, but if you want to use what you've been saying about Christina...well Norbert may not have had a broken foot or had to save his show, but it's not exactly like he gets to breeze through his performance. He's rolling on the floor, singing, dancing, jumping all over the place in GBS, slides down the stairs, etc. I was fortunate to go to a talkback after one performance and he sat w/ his bag on the stage and every so often he would fall onto his bag, he looked soo tired. But he gives it his all 8 times a week.
That and he gave the performance of the year(well Victoria was great to but she's not a choice...)
"If there was a Mount Rushmore for Broadway scores, "West Side Story" would be front and center. It snaps, it crackles it pops! It surges with a roar, its energy and sheer life undiminished by the years" - NYPost reviewer Elisabeth Vincentelli