This is something that's been bothering me for a while; I'd like to hear what others think.
In the Replace dialog, the "Replace All" section has a checkbox ("Close dialog"), and three buttons that control the scope of the search:
[In Selection] [In Session] [In Document]
"Selection" and "Document" are self-explanatory; "Session" replaces text in all currently-open files.
Why are the buttons in this order? Intuitively, I would expect them to be ordered in terms of increasing scope: selection, document, session. I don't see why the current order would be preferable---I've never even used the "In Session" button in actual work.
--Daniel