Hi WK,
About statistics, what I think what you actually calculated is one over the probability of getting the proper three sequences of A, B and T in a single trial.
But the A, B and T sequences are presumably constructed independently, rather than all together in a single trial? And on a planet sized body there could be literally bazillions of trials? And there must be a number of unknown factors (given our lack of certainty about conditions on the ancient Earth) governing the construction and breaking down of nucleotide sequences?
Unlike creationists, I don't think we're in a position to calculate probabilities of even simple sequences like A, B and T, but I think your number probably represents an extremely low lower bound.
--Percy
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