And 'best dance' is subjective anyway.
What is the 'best dance' - is it the one at the top of the leader board (erm, not always no!).
I'd guess for anyone with a favourite, it would be quite easy to persuade themselves that their favourite did actually do a good dance - or at least showed improvement week on week.

I vote for my favourites. They are my favourites because they are the best dancers! And I vote for the celebrity NOT the pro.

I tend to have favourites (Roger Black, Colin Jackson, Jill) who often also dance very well and this year the same : way out in front Mark, but also love to watch Ray and also Carol : sometimes it depends on which type of dance they do too ie Peter in Ballroom is lovely to watch, but the whole show is wonderful entertainment and I suppose I favour the men more than the girls but I have no idea why !!! hot, hot, hot Maryjay ...

I would never vote for somebody who was quite obviously useless, no matter how much I may like the celebrity.

The couples I have usually preferred have normally been amongst the best dancers anyway - Jill and Darren, Colin and Erin, etc.

I always vote for the best dancer though they will usually be my favourites anyway. This series I've found it difficult to choose a favourite with so many talented celebs but I think that Emma and Mark are pushing in front at the moment.