The teacher (who is quickly becoming one of my favorites, by the way) stopped the class after the first run-through and said something like this....
"Most people groan when they think about adagio. Adagio can be very difficult because you automatically tend to focus on technique. How am I going to hold that extension? How can I do that without falling over? You want me to hold that for how many seconds?
But everyone has days when their technique just isn't there. And on those days, use them as a gift to focus instead on your arms, your épaulement, and your musicality. Those things are what make you a dancer. Anyone can do a beautiful port de bras, but if you don't do it musically, and have that quality of constant movement, who wants to watch that? I'd much rather watch a dancer whose cambré to the back is only a few degrees, but it melts, than watch a dancer who can bend like a pretzel, but who "sits" in the position."That next run through, I focused on wrenching every bit of movement I had out of every single beat of the music, and you know what, it worked. My adagio felt different, looked different, and I even got a shout-out from the teacher on my musicality.
I'm going to try really hard to make the mental switch when I'm having an "off" day. Both my knees have been hurting recently, so I feel I have more "off" days than "on," which is frustrating. But on those days, if I can think of them as "music and arms" days, I think I will have a MUCH better experience dancing.