I have just one question: why did you swap your excellent Nova fins with outdated, crap jet fins?
Was it suggested by the instructor, or you just did think that they were the "do it right" thing?
You know how much I enjoy your posts and the great respect I have for you, but let me point out that calling something "crap" without (1) an objective analysis of advantages and disadvantages and (2) understanding the needs of the diver is just not beneficial for others
Although less efficient with some type of kicking, rigid non-split fins are way more precise than split/flexible fins. This is particularly beneficial with back kicks, helicopter turns, and modified kicks. Besides, although less efficient, using them is definitely not too much of an effort whenever high power is unnecessary. Frankly speaking, I can think of very few conditions when high power is a must - like a strong current; but a physically well-trained diver can easily use rigid non-split fins even in high current situations. So, if precision is important and the diver is in good shape, rigid non-split fins are definitely the best choice "almost always" (there will always be exceptions). Given that the most significant difference among various rigid non-split fins is buoyancy, as others pointed out, calling jet fins "crap" is at least misleading. Then, again, they are absolutely too negative in this specific case, and other options might be more optimal.
Between "crap jet fins" and "excellent nova fins," if I wear a drysuit, there is no doubt "crap jet fins" are the way to go for me. If I am wet diving, there is no point in using negative fins, but surely I would not go for the nova or other split/non-rigid ones. Precision is so much fun that losing it does not make sense.
I understand it's a matter of
personal preference, so feel free to use what you want - no judgment at all. But it would help much more to present advantages and disadvantages objectively and let others make their choices instead of giving judgments without explaining why
Peace & love, and dive safe!