This is one of the inherent pitfalls of relying on an open v closed economic argument. As did many other soviet satellite states, and the USSR itself, Czechoslovakian production, and its export, was split. Inwards, towards Comecon, particularly for supplies of oil from the Urals and Siberia, externally, to the West, in order to earn "hard" currency for trading between the communist bloc and the "west".
I know from the on-loan unpublished manuscript on my desk, that, with regard to glass, one particular company did influence Czechoslovakian production, certainly before WWII, and knowing the quantities of glass imported by them, in the post-war period, if the design and, arguably, quality, was not good, they would not have bought it. They would most probably have sought suitable designers, and had the glass made elsewhere, much as did Wuidart. Thus solely looking at the "closed" sphere of economic activity, might well obscure what was happening, and provide the basis for the view that there was no good design.
It is perhaps a convenient peg, for suspending indefinitely, the examination of the role of the Communist Party, and its control mechanisms, and whether, rather than being wholly malign, there were some aspects that were beneficial. I think that perhaps the time is not yet arrived.
Text © Marcus Newhall 2005