Prior to Hoyle's stroke of genius, there was no proof that carbon can be naturally synthesized, therefore, how would the proponents of the Miller's experiment defend a claim that he used a "God-created" element--carbon--in his investigation? Therefore, without the Hoyle's contribution, Miller et al would be irrelevant.
This only makes sense if you have the deluded opinion that Miller's work was somehow intended to be some sort of disproof for the existence of god. Since this isn't the case the origin of carbon is totally irrelevant to Miller's investigations.
If you want to produce a totally naturalistic history of the universe then arguably the lack of Hoyle's nucleosynthetic concept is important. If all you want to do is show the formation of some organic compounds from inorganic precursors is possible in given conditions then there is no need to refer to nucleosynthesis.
TTFN,
WK
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