I can not speak for anyone else, only for myself, but I find Johns lab notes interesting and extremely thought provoking. It will take me a week at least to chew through that last diagram. So I find the lab notes more thought provoking than conversation lending. I enjoy and follow when the thread discusses functional and usable theory that directly applies to the machines we build. Especially when that theory is compared with experimental results.
However, yes I do lose interest when the discussion goes the way of the esoteric and wild theories that have minimal or no real world impact on our builds. I am just not interested in the theory of the universe without experimental results performed by those that present them. Too many unknowns otherwise.