I have just come across this problem again.
In version 22, attributes defined in an object were not added to the attribute list until that object was actually placed..
My office has just made the jump from 22 to 25.
In 25, that object just has to be in your loaded library and it will add to the attributes.
Great, because as we have been converting our old jobs to 25, some of the fills are getting messed up.
So somewhere between 22 and 25, the way it works changed.
So it's not really an idea that needs implementing.
It is a bug that needs fixing.
One of the forum moderators.
Versions 6.5 to 25
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Dell Precision 3510 - i7 6820HQ @ 2.70GHz, 16GB RAM, AMD FirePro W5130M, Windows 10