In light of this article http://affect3d.com/editorial/breaking-news-fred-likes-futa/ I guess it's only fair I answer my own questions
1. Its probably more accurate like others have said to think of it as surrealism
2. I guess I aquired it, and got used to it (surprising quickly), I was very anti futa, then changed my mind, so I don't think its hard-wired
3. It took a few tries to get used to it
4. No, just realised I had a greater capacity to suspend my disbelief than I had previously thought.
5. Well, the only futa who convinces me of her gender (so far) is Sayako, considering her size, not sure I could do anything for her