Interesting, Tim. Since there are equally secretive schools on the Japanese side, I've no problem with reserving judgement here. I'm only reporting on what I've experienced from some of the guys from within the mainline organization, and from viewing the video clip above.
Then, there's also the possibility that jin training may have found its way into that "alleged direct lineage" dojang in more recent years. But obviously we don't have enough information to go on, so everything is conjecture. Still, it's interesting to consider. Thanks for the tidbit.