Continuing the discussion from Wish compressed file:
This wish may also help with the Compressed File wish
SelDup only finds literal copies of each other, and not objects that are geometrically and spatially identical. A matching algorithm that would find geometrically identical objects would be a godsend. Two ways this would be beneficial. A) not storing geometrically duplicate objects in a file, just their spatial and meta attributes. B) Find geometrically similar objects and convert them to blocks, edit definition, update all block instances, explode them.
I have made wish requests for Blocks before. They are great, but have their challenges as well. Sometimes I don’t use them because I can’t see them changing and kick myself later. There is no way to update a group of identical objects without deleting them and re-array or re-flowing them.