I would not say that a course with one of the many Training Schools makes no difference at all. What I will say is it doesn’t make as much of a difference as the Schools like to make out.
The no.1 priority is someone who has the appropriate technical qualifications and experience. If you don’t start with that, you can do any Intensive Advanced Top Gun ROV course you want, and it will help little.
The other thing is that an ROV course is only good for applying for ROV jobs. There are many other jobs offshore (most of which are better paid than ROVs) so again it is silly to limit yourself to that career with a specific course.
Fibre optic course, yes, that would be good, man management, don’t worry about that you wont be in charge of anyone for a few years. Health & Safety courses, that would help – anything involving Risk Assessments, COSHH would be of use. Mechatronics seems to be becoming a popular qualification to have. High voltage working is also very handy.
Alas like the rest of the world, very little repairs are done offshore now, its all swap out cards at best or whole units. Anything showing fault finding training would also be relevant.
As it is, so many people are applying for so few positions, it is down to luck and right place at right time on some occasions.
As I said, I would look ate courses etc. that would help boost your technical qualification side, and don’t limit yourself to ROV, look at SubSea Engineers, Rig ET, Rig Electrician, there are many other jobs offshore, make sure the qualifications you get are relevant for applying to them too.