Technical diving is an attitude as much as specialist equipment. The main requirement is self sufficiency such that an issue doesn't turn into a problem and doesn’t turn into a disaster. Redundant gas and critical equipment, planning for problems, skills practice to resolve problems.BTW I also started a tech course but just could not get on with the twinset. I am small bodied and they were so cumbersome and I couldn't get the right attitude in the water (legs kept floating up), and it really hurt my neck. I would breath in and ascend then breath out and sink ha ha. My instructor was really good but it was just "not for me". The single tank works well in most environments unless shipwrecks or caves, or very deep. The theory however was great and I still enjoy reading the manual and digesting the information. Mostof the interesting stuff that I have seen is between 15 to 20 meters where you can stay for an hour and see loads and have a great time.
Backmount twinsets aren’t the only technology. A simple side-slung pony stage cylinder(s), using sidemount or even rebreathers which all provide more and redundant gas.
This is the point about DiveMasters lacking wider diving experience; looking after baby divers doesn't do much for your skills. You won't be going deep or underground to visit the interesting stuff such as wrecks, caves, flora/fauna, etc.Why go to 40 meters where you can spend 3 minutes???
If I’m visiting a 40m/130ft wreck I plan for at least an hour on the bottom, maybe 90 minutes. Why dive for 3 mins? We’re scuba divers, not freedivers (aka snorkellers).