I was an instructor working for a PADI shop in Colorado about 15 years ago. It was (and still is) common for our students to do the academic and pool work with us and then take a referral with them to finish the course on vacation. The paperwork for this involves signifying that the student has done the work by initialing each item and putting your instructor number next to each. This has to be done on both the student record file and in the student's logbook. That is an enormous number of initials and numbers. Recognizing that, PADI had some of the items (like the knowledge reviews) grouped together, with a statement with each group saying that if the same instructor did all items in the group, a signature at the end would work instead of all the initials. That is what we all did.
One of our students took his referral (a copy of the student record file) to a French island in the Caribbean. The PADI instructor there told him that his referral was not valid because it did not have initials and instructor numbers on every item. If he wanted to be certified, he would have to repeat all that work with them. He called, and we told them that the student had done all the work and that the signature was sufficient. Nope. We contacted PADI headquarters, and they called the shop and told them that the signature was all that was needed. Nope. The instructor said that getting a call from PADI headquarters in California meant nothing to him, because they were PADI Americas, and he was governed by PADI Europe. It went to PADI Europe, and they backed the French instructor, even though they used the same form with the same wording.
So from then on we had to initial and number every single item for every single student, because you never know when your referral is going to wind up in a French-governed area.