I've recently converted my opencbm package to TopGit, adopting a
workflow similar to that suggested by Martin. The main difference is
that instead of maintaining a separate long-lived build branch, I'm
exporting all patches directly on master.
Maybe it's just me, but I can't see the point in having a dedicated
long-lived build branch separate from master anymore. It certainly
made a lot of sense before TopGit, when all topic branches were merged
into the (messy) integration branch. But now, the topic branches are
cleanly exported into debian/patches.
Can someone point out an advantage in having a build branch, or a
drawback in not having one? The only thing I can think of is that after
running tg-cleanexport, all debian/* topic branches (which are based on
master) will automatically be marked as requiring an update. I don't
really mind, since they're bound to fall behind anyway. (I'll be damned
if I update them on every single master commit.)
 Of course, this discussion does not apply to throwaway branches.
* SynrG notes that the number of configuration questions to answer in sendmail
-- Seen on #Debian
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