Where they would normally dance in a straight line, Kristina had Colin walk round the outside of a circle, so that made the dance look different from a normal CCC.
When Colin was taking a pose and supporting Kristina's dancing, Kristina sometimes had him take a very wide stance, which is good in height terms, but again looks different to how the male partner usually looks, and it prevents him from being able to do steps compared to a man who has his feet together.
I'm sure Kristina could do better choreography if Colin was 7" shorter and Colin's dancing would look a lot better if Kristina was 7" taller.
IMO the producers have reduced what both of them can do, but they are doing their absolute best to minimise the damage.
I think they are both doing a very good job and I commend them for just getting on with it and making the best of it. It helps that personality wise, they work well as a pair.
Full credit to them but I'm not impressed by the producers pairing them.