I think this statement is another indication that Geno would like to play Stef and Kiah together, particularly against teams with a lot of inside strength, but has been unable to do it mainly because Kiah just doesn't reliably "come to play". When she does (e.g., the Duke game), the combination is very effective. Kiah didn't play much in the BET because her head was elsewhere -- very obvious in the final game against ND and was the reason why Stef played the entire second half despite sucking wind for much of it.
I had visions of a bracket where UConn would play Delaware and Tennessee in successive games. In those games, Kelly just can't be expected to defend or match up on the boards with EDD or Glory Johnson, so you would need Kiah out there for most of the game.
Now it appears that we will face at most one of those teams (probably neither), and that would be in the national championship game.
With the bracket as it is (no big brawny teams in UConn's region), Kiah's contribution probably won't be critical (and Kelly might actually do better) until the Final Four. But if Uconn faces Maryland in the national semifinal and Baylor in the final round, having both Stef and Kiah hitting on all cylinders will be crucial.