These GraphicObjects clog up the GraphicManager cache so it's effectively useless.
Round-tripping the ML bugdoc, this doesn't provide much of a speed-up by itself, but together with the previous fix it goes from 3:00 to 1:30 (in an optimized build).
c96e3e2 svx: make SdrGrafObj::mpReplacementGraphic swappable
include/svx/svdograf.hxx | 1 +
svx/source/svdraw/svdograf.cxx | 30 ++++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)