Does the Refresh Window (Records/Refresh Window) on the menu bar automatically flush the cache? I have a diminishing value list in a pop-up menu in a portal with an onObjectSave trigger that sets a couple of other fields based on what the user selected in the pop-up menu.
The script ends with
Refresh Window 
But this doesn't update the diminishing value list. However, when I manually click Records/Refresh Window from the menu bar, the diminishing value list works properly.
As might be expected, when I script this instead:
Refresh Window [ Flush cached join results ]
Then the diminishing value list works properly. But I'd rather not flush the cache.