Under penalty of death!
Signed this 18th day of December, in the year of our Lord, 1967, by
ROBERT H. JUSTMAN
I really love Bobby Justman's style. Hopefully his memo will put an end to these unfounded claims / excuses for lack of proper TOS research that "they often didn't know what they were doing." (which were also quite upsetting my stomach, I should add).
That passionate devotion to detail clearly indicates the contrary.
"The Tholian Web" is just another beautiful example, that you can either choose the "Thermian" or the "Brandon" approach.
For the Thermians - taking the on-screen information literal - there'd be enough evidence that the crew of the Defiant
also wore the Enterprise
The fact, however, that almost all the bodies of the extras were deliberately positioned to obscure the insignia, would indicate it would or should have been a different one, but because of schedule and/or budget restrictions that was probably not possible.