All IMHO., The threat of Enosis was part of the reason why Turkey had strategic interests in Cyprus, since they probably had concerns, possibly in the light of events up to and in July 74, probably quite reasonable, about Greek expansionism. As it was, the continued aim of Enosis , by some GC interests , including as late as 1967 big Mak Himself, in violation of the treaties, ensured divsion, and the obvious intent of the Greek led coup, representing the clearest possible violation of the treaties by Greece, finally gave Turkey the opportunity it needed. In that respect, probably at no time since 1955 (if not before) was Enosis going to be acceptable to Turkey, and all talk about Enosis should have died in 1960 at the latest, but the insistance on certain GC factions to keep Enosis alive gave Turkey the best grounds it coukld have wished for to keep Takism alive.
Big Maks' foreign policy ventures were a further factor, where his delusions of self importance as a world leader evidently pissed-off the USA i.e Kissinger big time, meaning that Kissinger was unlikley to move to support big Mak when the sh1t hit the fan, if not, as some argue, actively seek his removal. In that respect I think the evidence very clearly shows Kissingerw(and probably Callaghan, knew about the possibility of both the Coup and the Invasion and did SFA to stop them, which is disgraceful enough, but the evidence is tenous and the case somewhat speculative that Kissinger actively encouraged either.