I read this when Mark first posted it, and it swished over my head leaving not a trace.
I revisited it a couple of weeks ago, when I understood most of it.
Accordingly, I've started clicking the dome across on my little Digisix where appropriate.
Result: many more beautifully exposed and easy-to-print negatives in the past fortnight.
This is a slightly long-winded way of saying thank you to Mark for the article.
(the zonology in the discussion still swishes past though )