Problem exporting graphics to XML - dpi vs. impsize

Hi,

FM 7.2b128, exporting XML using schema.

I've had a structured app that I've used for a while that exports an impsize attribute (which I want) and does not export the dpi. The read/write rule is:

element "image"
{
  is fm graphic element;
  attribute "impsize" is fm property import size;
  attribute "impby" is fm property import by reference or copy;
  attribute "sideways" is fm property sideways;
  attribute "impang" is fm property import angle;
  attribute "xoffset" is fm property horizontal offset;
  attribute "yoffset" is fm property vertical offset;
  attribute "position" is fm property position;
  attribute "align" is fm property alignment;
  attribute "cropped" is fm property cropped;
  attribute "float" is fm property floating;
  attribute "width" is fm property width;
  attribute "height" is fm property height;
  attribute "angle" is fm property angle;
  attribute "nsoffset" is fm property near-side offset;
}

However, I've been making some schema/EDD updates and other changes and suddenly impsize is no longer exported, only dpi. I can't figure out anything I might have changed to cause this to happen. In the documentation, it suggests that I should put in a "specify size as" rule, so I did that, but I still can't get the impsize back unless I put in a rule to drop the dpi, such as:

element "image"
{
  is fm graphic element;
  writer facet default
  {
    specify size in in;
  }
  attribute "impsize" is fm property import size;
  attribute "dpi" drop;
  attribute "impby" is fm property import by reference or copy;
  attribute "sideways" is fm property sideways;
  attribute "impang" is fm property import angle;
  attribute "xoffset" is fm property horizontal offset;
  attribute "yoffset" is fm property vertical offset;
  attribute "position" is fm property position;
  attribute "align" is fm property alignment;
  attribute "cropped" is fm property cropped;
  attribute "float" is fm property floating;
  attribute "width" is fm property width;
  attribute "height" is fm property height;
  attribute "angle" is fm property angle;
  attribute "nsoffset" is fm property near-side offset;
}

So, is this is working, but is it the right way to do it?  Did I just get lucky before that impsize was exported instead of dpi?

Thanks,

Russ