No argument that Castro has achieved a lot more than Gulbaddin Hekmatyar, and the USSR did tend to support more progressive movements.  But in strictly cold war terms the USSR support for Castro (in the US sphere of influence) was no different from the US support for Gulbaddin Hekmatyar - in the USSR sphere of influence.  He was meant to attack the Russians.  He actually killed more afghans.  Guess who had the more incompetent foreign policy at the time.

Index of Frank's Diaries