When mail is opened with a letter opener, there is a strong likelihood that the contents of some envelopes will be cut. When this happens, the documents must be taped together again. This is even more of a problem when the documents are then digitized, since the use of tape may interfere with the scanning process. In either case, inadvertently cutting open documents increases the handling time required for incoming accounting documents.
The solution is to equip the mailroom staff with a small belt sander, which they use to sand open the edges of incoming envelopes. By doing so, there is no chance that envelope contents will be damaged.