I've looked at the video that David posted and when I approximate his process, my cutbrush also loses its ORIGINE values (IF I reselect it from the Tool History bin).
However, if after erasing, I simply click on the custom brush tool icon and attempt to Stamp-in-Place with the recovered cutbrush, it will still have retained its original ORIGINE values.
So, it seems that when a cutbrush is stored in the Tool History bin, it loses its ORIGINE values after reselecting it FROM THE TOOL HISTORY BIN. The ORIGINE x and y are both set to 0 (zero).
One major thing that goes unrealized here is the fact that the most recent cutbrush info (image and placement data) remains stored in memory, even though the tool selection changes (is no longer a cutbrush). But when the cutbrush tool button is reselected and there is/was a cutbrush lurking in memory, you can resume stamping with it, AND IT REMEMBERS ITS ORIGINAL STAMP IN PLACE (the ORIGINE place where it was first captured).
One more major thing that goes unrealized here is that when a cutbrush tool is saved into a button... and then reselected from the button, IT REMEMBERS ITS ORIGINAL STAMP IN PLACE coordinates (the ORIGINE where it was first captured).
These two facts reinforce the theory that cutbrushes (and animbrushes for that matter) seem to LOSE THEIR ORIGINE when stored in the TOOL HISTORY BIN (as David and others have discovered.)
Edit: and, at last, I see why the GEORGE command is called tv_BrushRestore!
Second Edit: David, if see this post, may I suggest you add one line to your Stamp in Place button?
1. Open the button to edit mode
2. Left mouse button click on the "Key:Tools Custom Brush Stamp in Place" command
3. From the menu choose "Insert a Command"
4. Then left mouse button click on the new line "None" and select "Type Script's Command"
5. In the Type Script's Command window that pops up type: tv_BrushRestore MODE "color'" and click OK
6. There should now be two command lines:
Command:tv_BrushRestore MODE "color"
Key:Tools Custom Brush Stamp in Place
7. Click ok to save it
8. Test the new Stamp button using the same steps you used before. What this does (in one click) is reselect the cutbrush that you originally captured, set the draw mode back to "color" and then stamp your cutbrush exactly in the place you originally captured it.