I learned a couple of afternoon's worth of welding (TIG and MIG, with a dash of spot) and looked at some books regarding it. I realized that I was staring into a piece of craft that would take years to actually master the nuances of, if I were even capable of it.
Very much, yes. Yes because of the probably different steels in a cruise ship versus a battleship, yes because of lifetime expectancies, yes because of stresses expected, yes because of inspection schedules. I probably don't have even a good enough sense of what is required to come up with half of where the differences would lie.