However in the CADORS report there is no mention of instructor or instruction. Instead check out by one pilot to another owner/pilot is stated as the purpose of the flight. In my days that was perfectly legitimate. Makes me wonder how the ligature of "instructor" was hung around the chap`s neck to get him convicted. Perhaps it was because a float plane was involved for which the appropriate licence endorsement was required.
And this is the point: If this had been a flipped over on the water after careless landing, there could be something to that. The "student" pilot might not be expected to be familiar with the characteristics of a good/safe or otherwise water landing, hence, the request for instruction. The "instructor" (whether licensed as such or not, but knowing for this purpose, a CPL is adequate) is required to teach and monitor new skills. However, nothing in what I read here suggests that this was a water flying event, it was a flying event.
If two pilots are flying together in a basic plane, it is a safe assumption that neither can abdicate responsibility for the basics - assure flying speed is maintained, and power to do that if needed is applied. If I, as a licensed pilot seek training, and as a part of that training were to fly a jet ('cause I never have), I would have no excuse for running out of fuel during a training flight. I have been trained to assure that the adequate amount of fuel is carried for the intended flight, and flying a different type is no excuse for my not doing that.
When I train on floats/flying boat/amphibian, it will always be to a pilot (as I am not an instructor). I always start by telling that pilot ('cause we're nearly always flying their plane) that they are also responsible for the safety of the flight. I will brief any non standard, or new maneuvers, but they are not exempt from responsibility. I am training pilots to be more skilled, and take more responsibility, so why would I relieve them of responsibility?
In my opinion this prosecution has overlooked some basic tenants of training. It sets some worrisome precedents, which are mostly based upon misunderstanding, at least of Canadian licensing privileges.