IndigoBlue:There is only one slight problem, in that freediving is focused on taking a full deep breath of air and holding it, whereas with scuba, Cousteau's Rule #1 is "Never hold your breath... ."
The historic NAUI and YMCA way of teaching scuba was first to teach you freediving together with many freediving skills, then to subsequently wean you onto the scuba gear. This is also how scuba diving skills were first developed, by Florida and SoCalif (and French and British and Italian) freedivers. That is also how I learned. We became freedivers first, then scuba divers second. This is also how I taught my wife, since I wanted her to learn the traditional approach as well, and I wanted her to get used to the ocean with fins, mask, and snorkel before being incumbered with tanks and gear.
There is a drawback to this approach, in that it tends to reinforce the breathholding practice, even during the scuba phase. The habit is unconscious. You do not realize you are doing it.
I do not teach scuba students to be freedivers first. I teach them "Never hold your breath on scuba." The reason is risk related and insurance related. And therefore that also rules out freediving training before scuba, in my opinion.....
I don't know.
This line of thinking makes me think I should perhaps turn in my motorcycle license.
I can't possibly successfully drive a car and then go and drive a motorcycle. I might forget to lean into my turns or something???
Bottom line is aquatic comfort is aquatic comfort no matter what you are doing.