Back when Birdforum was in its infancy I remember digiscoping being the majority and dslr's much less - times have changed and now we find the opposite. I've always asked why and stayed the scope/p&s route. What I don't care for in your basic description is the lable photographer = dslr or birder = scope/p&s.
I currently use a kowa 883 and canon s95 with a custom adapter. The adapter is easy on or off but when birds are around it is on, I'm always going for the sweet shot. I'm always studying the light and trying to get a position that will compliment the bird. I'm always looking for equipment that will enhance my ability to get the best possible pic. I love the way a digiscope enables bird study at distance and minimizes infringement on their territory, I think that with less infringement the subject is in a more natural state.
In the 80's I attached a 35mm to a scope, gave up shortly. About 2002 I saw some digiscoped pics on the web and had to try it, it has given me mega satisfaction in both birding and photography.