Families with nested families and file size

[mtr188297]

We are trying to reduce the size of some of our more complex families and I seem to have run into an odd situation. One of our family types are patient rooms that are fully adjustable (width, depth) and have visibility graphics options for certain equipment. These wind up being 7 to 9 MB families. In trying to reduce their size I started combining multiple nested families into one nested family. Where possible I would take the geometry from smaller families and put it into the larger one (in effect eliminating some families), so basicaly taking nested family A and B and putting their geometry into nested family C. I would then nest what I couldn't, so family D would get nested into nested family C. This would result in less nested families for the host family to track. However it turns out that my file went up a full MB when I did this. Is there a reason this happens? I would assume it would reduce the file size. How does Revit track all the bytes?