If both the
sending and receiving client support format=flowed, then paragr$ 
 Pretty sure I
recall Mouse mentioning at one point that he wrote his own MUA$ 
 
My MUA is mostly - entirely, from some perspectives - my own code.  My
MTA is partially my own code; my SMTP listener is mine, but I use
sendmail as a routing engine and first-level delivery backend.
However, none of that is relevant.  I went back and checked again (I
keep a separate copy of all mail that hits my inbox for some weeks).
Here is the Content-Type: from Dave's mail, the one that I was replying
to when I brought this up, as it hit my inbox:
Content-Type: text/plain; charset=us-ascii
Note the complete lack of format=flowed.  And I do get quite enough
mail that _is_ marked format=flowed; quite aside from it not being
designed to, there's pragmatic evidence it's not my code stripping it.
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