Well put, you make some valid points. I enjoy the friendly chit chat in the 'Anything Goes' forum, but I think it's out of place in the techincal areas. if somebody posts a photo of an engine in a technical thread asking a specific question about a broken or missing part for example, one-line responses like 'nice colour' or 'I'm jealous' and a smiley don't really add anything of value to the discussion. And you're right, it often takes the thread off in an entirely different direction.
Thank you for addressing this (and I'll be more carefull in future), and yes, this is an excellent site.