Your rod lift well just, fwompf, quits pumping overnight. Remember, the Boogie Man does some of his best (worse?) dastardly deeds down hole. The relentless bastard.
The doctor makes his house call the next morning. Rods are not parted, no way. The static producing fluid level is high based on the EKG. Close the flowline valve and pressure up on the tubing. Builds up to 400 PSI, bleeds back; rinse, repeat, same results. The diagnosis is one of two things, the down hole pump has worn out a seat, broke a cage, the barrel is cut out... or you've got a hole in the tubing.
Surgery is performed the following week. Rods boxes are badly worn and confirm the diagnosis. Mix aluminum paint with 5 gallons of diesel and pour it down the tubing. Put a wiper rubber on the hole below the slips and POOH (pull out of hole) with the tubing with your eyes peeled. Bingo. Not a hole but a full blown rod cut.
Bigger than Dallas.
A tubing transplant is performed, new DHP from inventory, the old pump is sent to the lab for a biopsy. Rod boxes are replaced, rod guides are installed to eliminate a similar problem in the future, the patient is revived and put back to work with no recovery time required. In and out. Day surgery.
Sadly there is no health insurance for this sort of ailment. Pity, that.