Personally I don't really care whether people vote for the dancing or just their favourites. It does seem a bit wrong though that
so many people are surprised and disappointed with this particular result regardless of whom they voted for.
Negative voting alone wouldn't work. SCD is a positive show and people like supporting individuals. Unlike BB which runs on hatred to a significant extent (and where most of the votes are head-to-heads anyway), SCD wouldn't get the votes in on a negative system. Apart from the 'F**k the kiddies' message that sends, having a small number of voters just increases the influence of nutters.
A couple of suggestions to make things less frustrating:
-Dual voting: you can either vote positively or negatively. That would counteract some of the 'noticeable because s**te' votes. So eg the Jan-support votes would be a spread of pro-Jan votes and anti-Georgina votes. But really I doubt people would use negative votes much when there isn't a tie at the bottom of the table.
-Allow some 'topping off' before the voting closes. So the 3 or 4 top pairs at the start of the second show would announced safe, and that would wake people up to voting for those who hadn't been.
Both of these might be plausible options as they'd probably lead to more votes if anything. (Are you listening Beeb?)
But really the important thing to remember is that democracy doesn't work.