I love how Thomas Young is described as 'the last man who knew everything'. My response to the question you pose in your article of why this error remained in textbooks is not that it was deliberate, but that in the field of science it is possible to say the same thing in a variety of ways and deliver correct answers in a variety of ways. Plus the path once chosen is stubbornly held onto when changing it does not fix any real problems, even when not absolutely correct.
Case in point is your own position that the '1/2' should not have been used, that in fact it is wrong, while in reality it is an otherwise correct way to measure actions against one another - as long as the same method is used. It is 'only' at the overall perspective of our understanding everything fully that we better get it absolutely correct. Said differently, this 1/2 remained in place because it had been instituted.
A similar story is found with the Year Zero. Scientists still reject the Year Zero in general, while the scientific evidence shows rather clearly that Year Zero was indeed really there [in the supported perspective, there are only 9 years between January 1, 5 BCE and January 1, 5 CE]. No one wants to change the history books by adding that one year and so a push-back is often in place trying to censure those acknowledging science is incorrect in supporting this option.
Allow me to play the devil's advocate a little more in stating that hindsight is 20/20 and once we get E = mc2 and recognize it as true, then we can look back in time and see that this was already recognizable in the work of others. The finer point is that truths can be told in more than one way, and folks like to present something as new when in reality there was nothing new under the sun but presented in perhaps a better way.
As a final note, if I can finish this with my pet peeve of the same light, about the ToE already being known in ancient times. Of course, it would not be expressed in modern details, but the ToE is like E = mc2 in that we can look back in time and recognize that others recognized the overall setup already.
It means that there are indeed two levels in which we must express the ToE: The specific forces are based with matter itself, while gravity is based on the overall setting of matter and not the specific level. Or with GR and QM, GR is where the overall level provides us information about the collective behaviors (including in specifics), while QM provides us information about the detailed level that cannot be generalized.
Same for rolling a die. Roll it once and we have uncertainty about the outcome. Roll it a million times and we have certainty that 3 will get rolled one-sixth of the time. To ask if rolling a die delivers certainty or uncertainty is a question like asking if you were born because of your mother or because of your father? Scientists like to get a single answer, and unification is indeed available but only at the specific level and not at the universal level.
Many ancient peoples created the pyramid to show this setup (in Egypt, Nigeria, China, Meso-America). The word pyramid has been translated as "One that comes forth from height" meaning that the 1 is placed higher up, in the air, while the specific parts are found at ground level. Building from the ground up, the top position is either 1 (the top position) or even 0 ( the top pointing to the sky).
Same can be seen with colors: mixing red, blue and yellow, one ends up getting a fourth outcome: gray.
Or having four groups of three groups: fathers, mothers, children, families.
The synergistic outcome is distinct but not a separate reality.
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Good luck with your publication. Large round of applause.
https://medium.com/swlh/explaining-the-theory-of-everything-to-a-three-year-old-5e3046b8c1d4