"I think that a lot of people don't realize how disconnected the feeling of hunger is from your actual (very minimal) caloric requirements."

True, this is my observation as well.

"The hunger response can be trained away in about a week."

Unfortunately, it is quite easy to fall off the bandwagon in irregular conditions (holidays, vacations, a visit to an elderly relative who insists on feeding you). The adaptation to IF is, in my case, lost just after a day or two of non-IFing. And once it is gone, I have to undergo the week-long self-training again.