<bridgehead> "renderas" attribute doesn't seem to do the right thing

in my quest for flexible exercises, i decided to use a <bridgehead>
and use the "renderas" attribute to have a free-floating header with
whatever font size i wanted.

  first, i used the attribute-set "section.title.level1.properties"
to set the font size for level 1 titles to 24pt.  that worked fine,
the resulting PDF has massive titles for level-1 sections.

  but when i threw in a 

  <bridgehead renderas="sect1">Exercises</bridgehead>

that title was rendered in what looks like 16pt -- definitely
smaller than the font being used for section 1 titles.

  isn't that the whole point of the "renderas" attribute?  am i
missing something here?

rday