Eric and Jim interview
Spoilery in http://featuresblogs.chicagotribune.com/entertainment_tv/2009/09/supernatural-kripke-season-5-bobby.html
A quote...
MR: Does this affect Sam and Dean's relationship with Bobby? Are they guilt-ridden about what happened?
I think they are. Part of what's actually fun about Episode 7 is that there is some exploration of their new understanding of a little of what Bobby's going through. But it's actually done in a more fun way rather than in a heavy way. They get a more intense sense of what Bobby's circumstances are, but that aspect of things is kind of lighthearted.
A quote...
MR: Does this affect Sam and Dean's relationship with Bobby? Are they guilt-ridden about what happened?
I think they are. Part of what's actually fun about Episode 7 is that there is some exploration of their new understanding of a little of what Bobby's going through. But it's actually done in a more fun way rather than in a heavy way. They get a more intense sense of what Bobby's circumstances are, but that aspect of things is kind of lighthearted.