GUESTRex, that makes sense! I like it.

I have been wondering what this phrase means since I was a little girl, as my Grandmother always says it. Our version is:

"Too late!" she cried, as she waved her wooden leg!

Usually it's said in a farcical situation, like if we were to forget to mix in sugar before cooking a cake or something.

We're from Australia, and my grandmother turns 80 next month, but she has no idea where it came from either! Seeing as most of the "too late"s have been NZ I think it might be a hemisphere thing!
But the asking to dance thing is a good one, it makes sense and next time I visit Granny I will see what she thinks!