Beats me, Man.
Sometimes when things are rollicking in one thread, it can carry over to another, I guess. Sort of like when a police officer goes from one extreme to another and has to shift radically to accomodate the change in "environment", maybe. (One of my best friends, a retired investigator, used to tell me about that and how hard it was. And I can see something similar happen on the boards, where people "surf" so many threads at once.)
And, keep in mind that a lot goes misunderstood when writing alone is the means of communication. More than 50% (some say 80%) of communication is not words, but tone of voice, body language, eye contact, etc. And none of that comes across in written word, unless the person writing takes pains to be especially expressive and sensitive to how things "may" sound, etc.
So, some of it can be chalked up to misunderstanding.