But from NBC/U's perspective, the WWE could garner those ratings on one of their other dozen cablenets.
Diluting the science fiction on the Sci Fi channel, turns it into just another channel with an occasional primetime science fiction show - same as many other channels. If you want to lock up that genre, that isn't the way to do it.
It's like owning a small mall with 20 specialty shops - each one offering the widest selection of products for their target market. The stores will have varying levels of traffic, but as the owner of all of them, who cares as long as each store is considered the best in the city for its market. If the individual GMs of each store cut back their selection in order to carry the best products from the other 19 stores, you'll end up owning 20 mini Wal-Marts. A handful of the stores will show improvement, but the net effect for you is a radical drop in total traffic.