In answer to your original post, I don't think many practitioners at my TSD organization know, or at least perform Oh Sip Sah Bo much. I don't think I have ever seen it done at an event, and I believe it may be considered a 7th dan form (!), which is somewhat limiting.
I did the shotokan "Sho" version (the "minor" according to JKA, but the "dai" version in SKI) at an open tournament and I don't believe most of the TSD students had ever seen it before, or knew it could be a TSD hyung (with some small changes).
As someone else pointed out, the TSD version most closely resembles Gojushiho Dai (JKA), not the "Sho" version, although anyone seeing any of the three forms would instantly recognize it.
I did have one comment, which is not necessarily limited to this form. Looking at the various videos, if there is any one thing which jumps out, it is the footwork of the Tang Soo Do version when compared to any of the Japanese kata. The Japanese kata, pretty much across the spectrum, tend to have the feet barely lift and quickly get back to ground. The base foot tends not to move or adjust before the other foot moves. The student performing generally tries to maintain an even height (save those positions when you might stand erect, etc) throughout. When watching TSD hyung, I think there are many circumstances of an actual step, with the foot elevated in an almost exaggerated stepping motion. The performer tends to bob up and down. The feet shuffle and shift. Combine these, and the hyung looks a little jerky and disjointed at times, although there is obviously power.
Although some of what I have described as the Japanese way of doing kata has a practical application, some is undoubtedly simply for the flow and appearance. I'm not trying to claim either way is superior or inferior. However, don't you think that the TSD forms would perhaps benefit from some effort to take lower steps, smoother flow, etc?
I've done several different martial arts, and I consider TSD my central style.