Thanks for bringing this up. I noticed the behavior is different between versions of PAC Display, and I'm looking into finding out why. Had you been using an older version and noticed this changed when you upgraded?
Seems to me that ideally, which way it behaves should be selectable by the person building the project. As you mentioned, I could also see how in some cases it would be nice to have it "retain" the previous value entered by the use and other times not. Thoughts?