Blackwood
Contributor
...NAUI [is] a little better on this one making divers take this before their technical courses
I know quite a few NAUI Tech 1 divers who haven't taken NAUI Intro to Tech.
I never looked at IANTD in much detail, but I suspect they also have a similar intro course.
I think IANTD's Deep Diver course is similar to some of the Intro to Tech courses offered by other agencies.
But, like most other agencies, what you get can vary from one instructor to the next. My IANTD Deep Diver course involved close to 100 hours in open water, about half of it with the instructor, and the other half just training with my classmates.
It was taught by a GUE Tech/Cave diver in much the same way as DIR-Ftech (very rigid skills requirements, equipment requirements, etc.).
I wouldn't expect all such courses to be as intense.