The only time I've ever heard of a passenger enquiring where his/her planeside bag was when another pax has picked theirs up inadvertently, if the tag came off in the cargo bin or if it was some how buried with the other bags because of shifting. In the case of the misclaimed bag, a page across the airport solved that problem and in the case of the bag where the tag fell off, it's more complicated. If the untagged was found in time, the ramp agents can "make it work" and get the bag to the customer. If not, the bag will go to bag claim as untagged bags cannot be brought up into the terminal.

I'm not sure what other DCI carriers are doing in the former DL hubs, but I know all plane checked bags are being "scanned" just like the normal checked bags. IF your bag should be misplaced, they're traceable by the barcode, as before they were never scanned and therefore impossible to find with technology. The other nice thing (at least for Mesaba) it would be virtually impossible to "forget" to load the bags. Why? Because the ramp will fill out a form with the bag counts and their location and deliver that form to the pilots. We won't close the door with out it. And if for some strange reason, it's missing planeside bags, it would send up a red flag.