We've been told any action reasonably expected to elicit a violent response

[Jim Lane]

53. Your interpretation of the First Amendment is too narrow.

You write:

The specificity and the intensity of provocation is the key, not the speech or the reaction. The KKK can march through Skokie with their white power signs and chant about the supriority of their beliefs, but they aren't protected if those signs are specifically derogitory (as in <targeted group> always <unspeakable acts> ) and otherwise verbally assault people, their families, their culture, and their activities in the crowd as they march by.

That's not how American courts have applied the First Amendment. The speech you describe (the highly offensive signs) would be protected.

There's a limited exception that's not based on the "intensity of provocation" but rather on the circumstances. The exception can be roughly stated as "a clear and present danger to public order". If I want to carry a sign saying that the LDS Church is a Satanic cult and that Mormons commit unspeakable acts, I can do so, even if I'm parading through downtown Salt Lake City with it. BUT if Joseph Smith (the founder of the LDS Church) is being held in jail, guarded by only a handful of deputies, and there's a large angry anti-Mormon mob assembled outside, and I give a fiery speech intended to incite the crowd to go beyond general hostility to Mormons and instead to storm the jail right there and then to drag Smith out and murder him, then that speech can be prohibited.

Furthermore, there's an exception to the exception. The courts generally won't enforce a "heckler's veto" (as termed by Harry Kalven). In the (historically accurate) Joseph Smith example, the clear and present danger to public order came from the people whom the speaker was inciting to action. If you allow suppression of speech based on the reaction of those hostile to the speaker, then anyone willing to resort to violence can shut down the peaceful speech of nonviolent advocates of different ideas. It's as if abortion opponents, by threatening to bring guns to a reproductive rights rally and start shooting people with pro-choice signs, could thereby empower the authorities to prohibit the rally. That's not the law in the United States, nor should it be.