Much more clever than mine. But.

• I only run that code once, the screen flashes obnoxiously once for each property (even though I'm only changing one) (yes, I did turn off screen updating).
• The instance of the property in the header is not affected at all.

Whoopsie, cancel......

My code is updating the headers, with almost no flickering (just the cursor). It's a long story of several errors why I thought it wasn't.