We all have to admit that the PNC's tenure from 1964 to 1992 was really friggin terrible by any measure. We can point to some instances of competence or what not but largely it was pretty awful.
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Correction. It was hell between 1978 and 1990. Guyana was in a good place before then, and Hoyte blocked the Jagan communists from turning Guyana into Cuba. Had Cheddi directly replaces Jagan look at Cuba and see what Guyana would have been today. In fact Guyana would have been worse, given that it started at a more backward place to begin with.
Caribny, the Berlin wall came down in 1989 and the Soviet system with the Warsaw Pact countries came down with it. The Socialist International (the fraternal communist parties controlled by Moscow) was not what it was. The PPP supporters in the Diaspora was meaningful at that point. So I could not see how a Cheddi Jagan-led PPP would have taken Guyana the Cuban route. Note that Michael Manley in Jamaica was suitably changed also and I don't think Cheddi would have been not affected.