kentina domination never happened. or at least it wasn't consistently in every single leg according to my memory.
Nick/Starr and Ken/Tina both had three firsts followed by or preceding three 5th-6th place finishes in a row, but Nick/Starr's were earlier so had more dead-weight teams. After that Nick/Starr had the FF (which isn't really domination) and a third place, so they did have fair competition (and Toni/Dallas were much stronger than Jaime/Cara or Kisha/Jen or Mark/Michael).

Compare them to this season, where Tammy/Victor and Margie/Luke only fell below 4th place ONE TIME COMBINED, which makes them far more predictable front-runners than even the Hippies and Eric/Jeremy.