I used to work with another instructor teaching students in quarry-like conditions who made the same argument. He had never really done much else himself, and I disagreed because I had a lot more ocean experience than he and agree with Lynn:
I recently spoke with a tech instructor who told me that he did most of his diving, all the way through advanced trimix, in quarries and quarry-like locations until he moved to Florida. Now you may think that Florida is as easy as it gets, but he said he felt like a raw beginner when he got there. He just wasn't prepared for that kind of environment.
We are all beginners in new environments. But if you have only dived in warm, clear, calm water, you will not find cold, murky surf easy.
I recently spoke with a tech instructor who told me that he did most of his diving, all the way through advanced trimix, in quarries and quarry-like locations until he moved to Florida. Now you may think that Florida is as easy as it gets, but he said he felt like a raw beginner when he got there. He just wasn't prepared for that kind of environment.