Not sure that is correct.
Michael, on several occasions over the last decade, I have written to the US Embassy in Canberra, emailed, and when I can get near them, asked at the Consulate, how long one has to take 'between' six month stays, to no avail. The answer always is that I can stay for six months, per entry. No one has ever answered the question I asked, how long between entries.
I am getting the feeling that there is no set time, and it is decided on each entry. Something which I find most unsatisfactory. I want to know before I leave home, what I am going to expect on landing at LAX.
But that's the US system for ye. Like it or leave it!
Lifey