By research we learn that the reissued passport of Samuel Sokobin was signed by Ernest Price. Thus he was legal in China but it was really the job title of American vice consul which enabled Sokobin to sign the passport of my great-grandfather a few months later, in 1917.
Yes, we citizens of the United States do trust our representative government for the hiring of appropriate embassy personnel and the rules of them. I really do not need to think twice about what government official signs my birth or death certificate or other legal paperwork. The people may come and go for whatever reasons but it is the office and authority of the government that makes the passport valid. I do not recall this being an issue. Needless to say.