An H1B is considered a “dual intent” VISA - the holder can say that it is temporary if he wants to or he can count it toward permanent residency and citizenship. The 5 years of permanent residency required to apply for citizenship is considered to commence when the H1B VISA started, and NOT when the green card is given. So there is a “backdating” of sorts that takes place.
Interesting
You do have a source for your thoery of course ???