Well, Leeneia, it does help enormously if you are, or ever were, a dancer, as you'll the know what is required, as Steve G suggested in his most recent post, and whether you can still dance or not. Within the 2 bands I play with, we have some very talented musicians, but not all of them actually understand the format of how a dance is arranged, e.g. how many bars before you change tunes, how many bars fit one run of the dance (or even how many bars in each tune!!) Those who DO understand all this usually are dancers themselves and know how the respective dances go.
My background is having a Scottish mother, who taught Scottish Country Dance sets to a mix of Scottish ex-pats in England and anyone else who wanted to learn, from when I was maybe about 6 or 7 years old. (Good time to learn while the brain cells are not starting to die off!) Now, after 30 + years back in Scotland, (and 50+ years older!) I play in 2 Scottish Ceilidh bands. In my mother's day, callers were unheard of, as you'd have been going to classes long before " the big dance" to learn all the moves. And if you were still clueless on the big night, one of my Ma's pals would literally push you through it! But now we have callers for most Scottish ceilidhs, tho maybe not for Royal Scottish Country Dance Society clubs, where, as in my mother's day, they will have learned the dances at club nights beforehand.
And finally, you may know a particular dance inside-out,upside-down, and like the back of your hand when you are dancing it yourself, but it's entirely another "can o' worms" trying to tell others how to do it. Apart from anything else, you've always got to be a couple of bars ahead of the next move.