I believe SF need a change in training. Right now is too hard to train SF.
Using your own logic PF has no single position training why should SF have one?
I would like my PF to have JS training but I have to play him out of position for that also as I want them to shoot ok also.
The training system at the moment favors edges as it seems and that's how it should be
Because, as I mentioned and you've ignored, PF training is nicely bundled with center training.
Jump Shot for forwards, you're not paying attention to all the training options out there.