Uwe: I've never used e-cigarettes (at least I've never "inhaled") - is it really a viable alternative to nicotine ingestion?
No, it's an alternative means of consuming nicotine, but without the carbon monoxide, "tar", and thousands other substances present in burnt vegetable matter. The reason it works for many people where other nicotine replacements such as gum or patches fail is because it mimics the habitual hand-to-mouth, inhale/exhale behavior as well. The reason it doesn't work for everyone is because it's missing some of the other psychoactive substances (minor alkaloids / MAOIs) that are present in tobacco. This results in some withdrawal symptoms for many people who switch. Most folks I know who've switched did it somewhat gradually, substituting their for more and more traditional cigarettes over a period of days to months, until they simply stopped smoking traditional cigarettes.
Seems from my uneducated reading on the subject that e-cigarettes are just another vehicle for said addiction
Yes, that's more-or-less true, but so what? Nicotine isn't the problem with smoking, the combustion products are the problem, and there's no combustion here. Nicotine by itself is about as harmful has caffeine, which is to say no very. There's actually evidence that it may be beneficial in some older folks, see
here.
And my second question: is the implied dynamic in your response generally the case for long time e-cigarette users: do "vapers" generally switch to e-cigarettes without any additives after a period of time.
There's almost no "generally". The type of hardware used, style, flavorings, nicotine concentration used, and so on are all infinitely variable and customizable. One of the important factors in successfully switching from smoke to vapor is finding a flavor that is
much more appealing than smoke to a particular individual, but there's no way to predict what that might be.
Some people taper off the nicotine entirely after a while, others do not. I'm in the latter camp, although I've reduced it down to about 60% of what I started with. I've tapered off the flavorings instead, because they're the biggest unknown. They're all food-safe stuff, but just because something is safe to ingest doesn't mean it's safe to inhale.
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