Great question. It's been a few years since I operated a commercial diving business in Vancouver, but I never had a call for "occupational SCUBA." Diving for occupational purposes (outside of recreational diving) is done in a manner that is "job focused." In other words, the customer wants a particular job to be performed. It's up to the diving contractor to itemize what equipment is best suited for the job. Sometimes this is SCUBA, but at other times it may be surface supply (air, mixed-gas), or even saturation. The Client is less concerned about how the job's done, than he is: Can it be done? What's the timetable? and At what cost?
I think when you restrict the tools available, you restrict the opportunities. An analogy would be someone who wants to become a carpenter by taking a course on hammer and nails. What do you think the job possibilities are? Not a saw, just hammer and nails...
I would also be interested in the credibility of the Instructors involved. Have they maintained a living by working in the "occupational SCUBA industry,"or is this just another way for a SCUBA Instructor / LDS to turn a buck?