That is exactly what I would expect fisheries law enforcement to say.

Hopefully a local officer checking you would consider other variables. For instance, I own a 21' boat that drafts 2.5 ft, maybe a little more. There is no way I'm going to get out of the Ford river in my boat, nor am I going to lauch at Cedar river and run 20+ miles up to wherever it is south of Ford river that I'm going to fish. Therefore, I have to launch at Esc/aronson Isl (slot area) and run south to fish a non slot area. If I was ticketed for this fishing practice, I would certainly fight it.