In practice, though, a mixture of both versions of the chemicals is the easiest to make, and from then it would have to be further purified to produce a usable sample of (S)-nicotine.
Yep, synthetic nic will be a 50/50 mixture of (R)-nicotine and (S)-nicotine. Separating them is exceedingly difficult (and therefore expensive) to do and would increase the cost by several orders of magnitude over the price of the synthetic 50/50 mixture, which is already several orders of magnitude more expensive than straight (S)-nic that's simply extracted from tobacco.
If this last step wasn’t completed and a mixture of both types was used, the finished e-liquid would only have half the strength advertised.
That's not quite correct. (R)-nic is about half as active/effective as (S)-nic, so a 50/50 mixture will be about 3/4 as potent as straight (S)-nic.
Without the plant-like taste from the impurities creeping into the flavour, there isn’t as much need to use tons of flavourings to produce a palatable e-juice.
Uhm, what kind of crappy (natural, tobacco-derived) nic has this person been using? Quality tobacco-derived nic produces an entirely palatable e-liquid without any flavorings whatsoever.
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In the end though, the reason that synthetic nicotine won't vaping is simple: If it isn't a tobacco product, the FDA could ban it instantly as an unapproved drug or medical device, which is exactly what they tried to do back in 2009-2010. The only thing that saved it back then was Judge Leon's ruling in
Sottera that it IS a tobacco product.
