Genomicus writes:
The paper clearly explains how the Krebs Cycle is an optimal design based on the materials at hand, yet there is no reason to suppose the Krebs Cycle is not also optimal from an engineering standpoint. In other words, the statement that its design is a "very clear case of opportunism," does not, in itself, suggest that an engineer could construct a better Krebs Cycle.
I agree - but that simply means their statement is not relevant to AZPaul3's question:
AZPaul3 writes:
Is this the most efficient and effective way to break glucose into ATPs? With the evolutionary holdovers from pre-glucose and anaerobic processes I wouldn't think so, but then I'm not a biochemist.
Q: "Is this the most efficient and effective way to break glucose into ATPs?"
A: "It is the most efficient and effective way to break glucose into ATPs given the material to hand.
Do you see? It doesn't actually answer the question being asked.
(It is instead answering the question: "Is this the most efficient and effective way to break glucose into ATPs given the materials to hand?".)
As AZPaul3 says, there are inefficiencies in the Krebs Cycle.
But your quote doesn't address those inefficiencies.
"There is no great invention, from fire to flying, which has not been hailed as an insult to some god." J. B. S. Haldane