I copied a stock material to the project level and change it's material to .73" from .71875".  Then I swapped the material in the project spec group.  When I redaw everything so that the new material will take ALL my machining goes away; line bore, dado & screws... all of it.  When I zoom into measure the material thickness it is all correct.  The strange thing is that the cabinet parts did not size down to accomodate the new thickness and the applied thick back is now overlaying the end panels and top & bottom panels.  The thicker end panels have taken up the gap between the adjustable shelves and the case parts...  I have tried bringing in a new cabinet and it is doing the same thing.