I think there's a place for recaps - particularly at the beginning of a season, which you might be watching several months or years after the previous season.
However, I watched a Discovery show on dinosaurs a while back, and it literally repeated the same 10 minutes of video about 5 times, and that was the whole show. That was so ridiculous that it made me not want to watch any more of their programs.
I was also watching a Nat Geo show - Dr. Oakley Yukon Vet - where the first episode was basically a promo/preview, put together from clips that were used/expanded in the next few episodes. If I had known that, I would have just skipped the first episode. Perhaps that formula works better on live TV, but I was watching it on Hulu, so it was totally unnecessary! (The series itself is worthwhile though.)