I am quoting you because I know exactly what you are referring to and because your comments are the impetus for this thread.its theft when you dont credit the source.
Kajukenbo for example, the name itself credits the source arts
If I learn how to perform a rotating punch in Shotokan and how to perform turning kicks from taekwondo, and the various blocks from either/or, and some locks and throws from hapkido, put them together in a coherent way and call it "Dankenpo," I am not stealing, even if I do not say where I learnt the individual techniques from. So while not theft, it is disingenuous on certain level.
Now, if I throw in Taegeuk pumse and Heian kata, then it is stealing. If I claim that I made up the forms or create a bogus history for my art and claim that a bogus founder created the forms, then I am lying and stealing.
Generally, I find that when you say that the TKD pioneers 'stole' from other arts, that you are not correct in this. In the transition from whatever the original kwans called what they were doing (Tang Su Do, Kong Su Do, and Kwon Beop if I remember correctly) to Taekwondo, the pioneers created the Palgwe forms from scratch, then replaced those forms with the Taegeuk Pumse a few years later.
The kicks and punches are just kicks and punches, and I suspect that punches with a rotating fist and high kicking were all in Korea before the establishment of Shotokan and the Japanese occupation. The sparring rules in WTF, like them or not, are unique to taekwondo and cannot be said to have been stolen from karate. Since they created their own forms, those aren't stolen.
As far as the history is concerned, reading it carefully, it is apparent that they are retrofitting the term 'taekwondo' to to include all Korean striking arts so as to tie modern taekwondo to pre-occupation striking arts in Korea.
This is no different than if I were to call all European striking arts, regardless of the time period, kickboxing even though the term did not exist until the 1970's.
Really, Shotokan's biggest contribution to taekwondo that could not have come from techniques that were already known in Korea was the kyu/dan system and rank belts. Which of course were culled from Judo by Funakoshi.
The Japanese occupation did play a large role in the formation of the kwans and the introduction of the arts of judo and kendo to Korea, and aside from a brief reference to it happening prior to the establishment of modern taekwondo, that role is not discussed in the official KKW history. Nor would I expect it to be.
There are many things that I agree with you about but your assessment of taekwondo in this regard is one place where I will have to agree to disagree. I will leave it to you, Glenn, and those interested to hash out how much of taekwondo is actually based on Shotokan over in the TKD section where there are no less than five threads at any given time that touch on the subject.
Now, if you bring up the Haidong Gumdo historical accounts of the Samurang, I will definitely agree that they are fabrications.
Kumdo schools that claim that kendo with Korean terms came out of Korean sword work prior to Kendo's introduction to Korea by Japan are also either lying or passing on a lie that they believe to be true, though the Korean Kumdo Association website makes no such claims.
I am not familiar enough with other KMA histories to even attempt to pick them apart and will refrain from commenting on them.
Regarding the question posed in the OP, and regarding your comment about crediting sources, influences, and such, I think that it is best to be honest about and up front.