My mailreader (Pegasus) lines everything up, both when read and when
I reply.  However, a quick look at the actual headers:

|Sender: "LISTSERV list owners' forum" [log in to unmask]>
|From: Bill Jenkins <[log in to unmask]>
|Subject:      Leading blanks in Subject lines
|To: [log in to unmask]

shows what appear to be several spaces between the colon and the
first letter of the subject.  Someone else will have to answer what
the mailreader is supposed to do with them, but all the other msgs I
checked (both individually sent via many different mail pgms, and by
other list distribution methods) have a single space between the
colon and the subject text.
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Robert Earl <[log in to unmask]> | Our God reigns!
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