genx - doctype?

[Tim Bray <tbray@textuality.com>]

John Cowan and others have suggested that genx should have a call to 
put in a DOCTYPE declaration.  This would be trivial to add to the 
program but it bothers me, so I'm provisionally going to say that I'm 
not doing this because it's not Canonical XML and the use cases are 
thin.

So this is a chance for people to say "I'd like to use genx for XXX, 
but I can't withou a DOCTYPE because of YYY."  -Tim