I did not watch but if the quote is accurate I find it unimaginable. Most normal males would never think of their daughters sexually. I think for most of us it is part of the gene's... what normal father talks or thinks like that..... 
Nah, it's called the Westermarck Effect. Reverse sexual imprinting. Happens pretty much automatically - IF the father (or mother) is around the kids enough. (Same effect makes it difficult to impossible for siblings to see each other in a sexual manner).
What would be sexual attraction turns into intensely protective behavior.
