Peter,
I found this message in archives:
http://www.postgresql.org/message-id/flat/519C3D99(dot)9000304(at)gmx(dot)net#519C3D99(dot)9000304@gmx.net
and, as you recommend, tested a speed of building docs on a fresh Ubuntu installation.
50sec for make html
and 14min 50sec for make xslthtml
17 times slower!
Is it still a main stopper for moving to XML?
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Pavel Luzanov
pluzanov(at)postgresql(dot)ru