Hello again. I asked about Buford's age so that I could get an idea of where he is at developmentally in his behavioral habits. I'd say that two is young enough to learn—in time—"new tricks."
My boss thinks that Buford's reluctance to defecate outside may be indicative of how he functioned in his previous environment. For instance, if he lived in an apartment, he may have become accustomed to pooping while on a leash, on a sidewalk. Dog's learn by association rather than causation, so instead of thinking, "I'm outside—time to poop", he may be experiencing confusion about new circumstances as regards your expectations. He could also be used to only pooping on gravel, in a dirt pit, or simply in the yard he was raised in. In that case, he may now be experiencing what is called in the psychological world, "cognitive dissonance." This is the confusion that arises when two conflicting mental concepts must be addressed at the same time. Dogs really do have a rich and complex psychological world. Our guess is that Buford is simply trying to reconcile new environmental phenomena (your home, you, and any other factors surrounding his new life) with his already existing mental constructs and behavior (this could be anything from the person he is used to accompanying him while he poops, familiar smells and sounds while pooping, or certain environmental conditions that he learned as a pup to associate with the act of defecating outside). It may even be that no one took the time to teach him.
In short, we can't know for certain EXACTLY what it is that presents Buford with difficulty in this area, but we can draw upon and apply what is known about canine behavior to help him—and you—out. I would suggest trying various ways to help him associate pooping with outside. You might try simply saying the words "outside" or "let's go out" when you see him getting ready to poop. (It's also important to remember that when correcting a dog for any behavior, you only have about two seconds to do so. After that, the dog has no idea what you're talking about.) You could also try taking him outside on a leash to different areas in your yard or surroundings, letting him sniff around. This could give you an idea about what he may be used to in relation to pooping outside (if indeed he is used to it at all). Additionally—and I know this is sort of gross, but science isn't always pretty!—you could try taking his poop (when he goes in the house) outside and laying it in an area where you'd like him to get used to going.
I'm asking you to engage in empirical observation and scientific trial to solve this problem. If you have the patience (and I suspect that you do) to work with Buford, I think that you will resolve this issue and also find some satisfaction in participating in the fascinating enterprise of canine behavior. I'd also like to mention that Buford's problem isn't aberrant or rare. I work in a dog daycare center and I will sometimes see new dogs defecating indoors before they learn that we want them to go outside. They are just accustomed to the bathroom habits of their home and therefore need some time to adjust to the novel situation of being at daycare and the expectations that it entails. Dogs are smart and they can usually learn these new behaviors (my Lab is almost four, and I'm still able to teach her new things on occasion).
Lastly, I'd like to suggest a great book by Dr. Ian Dunbar, who is an intelligent and insightful expert on dog behavior. You can find it at this Amazon.com link:
http://www.amazon.com/exec/obidos/tg/detail/-/0876052367/qid=1048609143/sr=1-3/ref=sr_1_3/104-1234012-3611962?v=glance&s=books
Sorry about the length of this post. Keep us up-to-date about how things are going with Buford (cute name by the way!). Good luck!