I do something similar but instead of calling the folder DMZ I create a folder called “Dump mm/dd/yyyy” where the mm/dd/yyyy is a date 3 months or so from now (whever you feel comfortable with). Tnen I just go in and delete them or archive them as I feel on that date. That way the mail is there for a search during the intervening time frame and if I have to search for something I then move it into a folder for future reference and to avoid the pending dump. Personally I could almost get away with having all email come in marked for deletion and then I’d unmark it if it was worth anything.