Haven't seen it for years but as I remember, you get the letter count of your words even if your opponent gets a longer one. Perhaps I'm misremembering.
Although I didn't watch this particular game it should be noted that a different type of contestant is now entering.This contestant is called an Apterite and they are members of a website which replicates the game of Countdown and apparently you either play against the computer at various levels or against a fellow online opponent.In fact several of the eight times winners in this series are Apterites.
Just watched it, we're a bit behind. He did it totally deliberately, had I been the other contestant when the dope had to declare first I would have either matched him or gone under to force points on the board. I will bet it was a student bet, he'll be a hero at College or wherever.