`  ::Pneumothorax is a poor choice for comparison, as you say all causes lead to the same accumulation of air in the chest. All epilepsies do not lead to the same seizures, frequencey of seizures, prognosis, etc. But I can well see how a non-specialist might think they do. In fact the Mechanism section in Pneumothorax could easily be combined with Causes. The introductory paragraph of Mechanism could do with being much earlier in the article, for it is the first time the body of the article actually explains what a pneumothorax actually is (it would be good if one is able to understand the article without the lead) - it doesn't belong in mechanism as it is really an explanation of what the topic is. The contents of the second paragraph are not clearly mechanism any more than they are cause. The Causes section is unsatisfactory and the Secondary Spontaneous section little more than a list with the reader left clueless. The separation of Mechanism from Causes leads to repetition and has meant the writers have left the mechanisms for many causes unexplained. The whole article keeps repeating the primary/secondary/traumatic grouping. The general reader does not look for ``Mechanism`` and I do wonder if truly the ``mechanism`` for many diseases is only really of primary top-level importance in a subset of cases. For example, in Tuberous sclerosis the cause is defects in one of two genes, but the mechanism is the path from that defect to the tumours and other organ changes. ::On talking to a wikifriend last night, we considered another topic, which was in the news yesterday. Dementia. Again, a term for a group of diseases that have something in common but quite different causes, results, prognosis, etc. The article has no mechanism section but an extensive causes section. ::The official guideline Wikipedia:Please do not bite the newcomers does not contain an exclusion clause for James. Our editing policy ``Improve pages wherever you can, and do not worry about leaving them imperfect. Preserve the value that others add, even if they ``did it wrong`` (try to fix it rather than delete it).`` does not say ``Users who work hard to prevent mediocre articles becoming POV balls are permitted to demand talk-page consensus from other users prior to letting them make any edits``. The basic premise that underpins his actions is ownership and I'm sorry to hear that 1000s of medical articles being owned by one editor is price worth paying  for if Wikipedia relies on one editor ignoring policy and other editors turning a blind eye, then we are doomed. ::I am pleased that our new editor seems to be solid enough to shrug off his unfriendly welcome and made an edit that has survived about 10 hours so far. The prose says something useful but could do with being more ``general reader`` friendly. Now, I wonder who on Wikipedia took an interest in working with experts to help them make articles understandable by all?  ° `