A pair of shears would have dealt with that line a lot more efficiently.
Back to the topic of carrying knives. I used to carry a pocket knife all the time. On my first trip to Europe, in 1990, I carried (in my right front pocket) my newly purchased 3.5" Cold Steel tanto lockback. It went with me everywhere: on the plane, into museums, youth hostels, even a nightclub in London.
On subsequent travels, I swapped it for a more practical Victorinox Waiter or Camper. But I still had a knife. No one considered a pocket knife a weapon back then. 9/11 is what changed all that. Now carrying even a Swiss army knife with a 2" blade is a hassle in the city and when travelling. I don't even bother unless I'm going hiking or somewhere outdoors.
Back to diving. When it began to be a problem to take a dive knife to some dive spots, I was happy to switch to shears. No worries about issues carrying the knife when I wasn't diving and I was never super comfortable using the knife underwater anyway since there wasn't a practical way for me to practice with it as a vacation diver.