I am a bit puzzled by the occurrence of the term lhag pa’i rnal ’byor in gNubs-chen’s bSam gtan mig sgron (p. 15.6). He seems to use this word quite often. One marginal note here has a ti and indeed contextually he seems to refer to Atiyoga or rDzogs-chen. But he also uses shin tu rnal ’byor (e.g. pp. 24–25). He, by the way, already seems to presuppose the equation of Atiyoga or rDzogs-chen. So what is going on here? One possibility is that he just messed up between Atiyoga and Adhiyoga. In other words he mistook Atiyoga for Adhiyoga, and that is why he rendered it as lHag-pa’i-rnal-’byor. The other less likely possibility is that Adhiyoga later on became Atiyoga and indeed rDzogs-chen was initially called Adhiyoga. But in terms of relative chronology, I think, this is less likely. We have Mahāyoga, Anuyoga, and Atiyoga already in the writings of authors that predate gNubs-chen. Rong-zom-pa, by the way, renders it normally as Shin-tu-rnal-’byor. MW does record adhiyoga but only in the sense of “a particular constellation” and has nothing to do with any yogic practice/system. Negi does not have any entry under lhag pa’i rnal ’gyor either. Any thoughts out there?