dancingalone
Grandmaster
If you put a TSD practioner outside of a Kata context, he is doing the same techniques as a Chang Hon practitioner, because TaeKwondo was a mere name change, alongside new Korean katas.
Is he? It's been years since I've been active on this board but I recall reading some posts written by Grandmaster Weiss about the Chang Hon system. He was quite adamant that General Choi had very detailed specifications for each move or basic. That doesn't mean that a Tang Soo Do practitioner can't have the same level of detail in his own learning, but I don't think TSD is as cataloged and documented to the degree that General Choi's system is.
What happened is that some of the old masters were reluctant to adopt the new Chang Hon forms due to politics. If they weren't, there wouldn't have been any Tang Soo Do labelled schools left, because that is the main difference.
You may find that a TSD practitioner is better at X, but this is due to a difference of emphasis, not content.
I will disagree with you with the caveat that not all Tang Soo Do is the same. The groups that retain a greater connection to Hwang Kee's Chinese influences are softer and I do discern a different in their movement from taekwondo people.