I think this is one week where Kellie isn't guaranteed to go through against either Katie or Anita. Because there are two dances, it means each celeb can choose the one that suits them more.
Katie has the waltz (and Charleston but I imagine the waltz will score more highly) , Anita the salsa and VW/foxtrot and Kellie the rumba/American Smooth/AT.
I imagine Kellie would do the AS (I think she'd be mad to opt for the AT) and Anita could choose either but I think the VW might be a tad easier.
In the dance off, Katie and Kellie (assuming she does the AS) will do ballroom and Anita could do either. I think Kellie would beat Anita but it could go either way against Katie. On the other hand, the judges may throw their hands up, decide Kellie is now surplus to requirements and do a Patrick Robinson with her. You never know.
I've thought about this way too much.