I understand the need to keep threads in the same general realm...but I think thread drift is a necessary part of online conversations and attempting to curb it kills conversations.
And I like thread drift. Usually. (Unless I started the thread, then I want very specific answers to my question only

. Only a little true)
Non e-hell example...
A board I frequent deals w/ pets and their problems; many of the posters are involved in pet rescue and they're a great source of advice for all sorts of questions (from "why is my cat using my laundry as a litter box" to "how do I get sap out of dog fur") and just general conversation ("hey, what did you think of the flyball championship", "Great, El Pupus Extrordinare just regurgitated beef into my shoe").
Last week we got a question about "how can I keep my dog from doing X unwanted behaviors, and don't even bring up getting him fixed because I won't discuss it"
Not only does the question of "is the dog fixed?" going to directly affect the answer, the reasons the dog isn't fixed (whether it be a health concern, desire to breed the dog, finances, etc) will also affect the answer.
Yes, it is pointing out that the person who owned the dog was "too bone-headed to think of such a simple solution " but it was also relevant to the conversation at hand. And cutting it off like that ties the hands completely.
(and yes, it also increases the odds [to 100%

], in the above situation that the dog owner is educated, against his will, on why he should consider fixing the dog. And I can understand he doesn't want that discussion...but those are the hazards of opening up something for discussion)