Quote Originally Posted by dwhitlow View Post
Decades ago I passed my driving test in a Hillman Imp and my license enables me to drive automatic cars, cars of any brand, vans, small trucks, and tow quit a big trailer. Not a singe extra course was required although my reversing efforts with a small trailer were funny to watch!

I qualified as a BSAC diver with BCD and single tank, and then added a pony, swapped to wing and twinset, and no 'skills development course, or 'speciality' was required.

When you consider an rebreather is just a wing with a tub of lime, some oxygen sensors, a few electronics, and a solenoid I'd argue any 'cross-over', or unit specific qualification, is merely an opportunity to support a diving instructor!
I see your point but for Mod 1, there are all the nuances of the unit that might not be immediately aparent until pointed out.

Mod Mod 2 and above I dont agree with unit specific, those courses teach generic theories rather than specifics so they should not be unit specific