I've felt basically since learning about Fundies that the scuba industry really could use an equivalent for the typical vacation diver. I'm sure there's a large number of people out there who are interested in being the safest diver they can be, but also will only ever be diving a rental jacket BCD with yoke regs in standard rec set-up.
I don't think you really need to "evaluate" instructors. Focus your search on OW instructors who also do tech diving. They will understand what you're looking for.Sure there may be individual instructors doing that as part of their PPB couse or similar, but SB in general makes it sound way easier than it actually is to evaluate instructors prior to a lesson .....