HC - I just wanted to clarify that being a trainer on a SAR L2 does not make you a SAR trainer on the L2 which is what your post rather implied
Definitely not a SAR trainer. And old piloty adage sprinter to mind "never assume - check!"
isn't that even more important to do in less than CAVOK conditions so they gain experience?
So what you are saying is that passengers' safety should be sub-optimal on that one flight in order that the pilots can do some "on the job" training to improve safety overall? Unfortunately the passengers on that one flight don't like that very much. I will agree that it probably would be good for pilot competence but unfortunately we are not the military (we can't do what we like at taxpayers expense, and we even need licences!) and have to do what the customer wants, which is increasingly restrictive. If you think about it, it is not really a tenable position to deliberately increase risk to passengers even slightly, or even at discomfort, just to satisfy some training need.
In my youth we used to, for instance, fly a whole rig trip AP out including a rather wobbly landing offshore, but for many years this has been verboten by both the customers and the CAA. We are not allowed by the CAA to intentionally degrade the aircraft's systems in any way with passengers on board. Once the CAA wakes up they will realise that that includes failing to make best use of the automation. (OK to be fair, they are starting to wake up to that point).