Wow Kate, that is incredible.
I am finding the same as a couple of other mums - Zara is happier if she doesn't nap. And she is happier next day too, cause her nights are longer.
Yesterday asleep 6:15pm, and slept til 6:45am - 12.5 hours in UNHEARD of in our house! And that was at least an hour sleep in! She is at daycare today, and I have requested that she doesn't nap unless her behaviour indicates that she really needs to. Will be interesting to see if they stick to that, the normal routine is that kids have quiet time which can include a nap, but I suggested maybe they could simply do some reading with her.
Interestingly, I have been complaining lately that Zara wont' play...not independantly, and not much with me either, she has no concentration, and is very disagreeable. This morning (and on the no nap days) she has been playing much better, both with us and on her own!