Believe what you want, but a detonation is an entirely different thing than excess pressure, which is quite easy to see occurring under the circumstances you mention. Many, Many times the word Detonation is used incorrectly to describe what is not truly a detonation at all.
Miller, the word that has been used in reloading literature for decades, when referring to a reduced charge of slow burning powder in a large capacity case that causes damage, is
detonation. You may not agree with the terminology, but that is the term that has been used to describe it for ages. It may be an incorrect usage of the word, but it is what has been used for as long as I can remember to describe the event.
So, your issue should be not as much with our usage of it as much as with the original writers who coined the phrase. We're just ignorant enough to continue with it.
SRH
