Dennis O'Connor wrote:

As I spoke about in my diatribe on preheating, yesterday; most of what is
passed from cfi to student is an old wives tale endlessly repeated... And
yes, some of those OWT's find their way into the pilots handbook from
engineers who ought to know better...

Pilot's handbooks are written by marketing departments, not engineers.

George Patterson
A diplomat is a person who can tell you to go to hell in such a way that
you look forward to the trip.