FTJoe, I agree with what your trying to say, and I surely don't feel offended. Nor should you be, bud. I whole-heartedly agree that to err on the side of caution is very prudent. Your point is well argued, and well taken. I must admit that I may have pushed it a bit when I wrote that using the e-cig exclusively would cause one's health to improve in EXACTLY the same manner as if one quits all together. However, from the evidence being presented so far I can't find too much to be worried about. There is a lot of really bad press out there, Like this idiot, and the FDA sure isn't helping, either. It's good to be skeptical, but I'm convinced that when all the smoke clears the e-cigarette will be exonerated completely. But thats just my opinion....
If you haven't watched the Dr Baron's interview yet, you should. Here is the link again: Dr. Baron
Dr. Baron is the Chief of staff at UCLA Medical Center. The reason I advice you to watch his interview is because he is VERY reputable. I realize that he is being interviewed (and possibly paid) by an e-cig company, but what he says about nicotine sums up very well what science says about nicotine.
Other appropriate links: New Zealand Study Nicotine info UK research on e-cig carts Study done on PG
With regards to your comments on how long nicotine remains in the system, and insurance testing, let me say this....
I have found several varying results concerning nicotine's half-life. The most conservative estimate that I've found says that nicotine's half-life is 2 hours. The most liberal opinions state that nicotine has a 40 minute half-life. The reason for this discrepancy seems to involve the individual. Some people metabolize nicotine faster than others. Thats why some folks smoke a great deal more than others. I smoked about 2 packs a day, but a friend of mine only smoked half of that a day. She may have metabolized nicotine slower than I did. But my reason for bringing up the short half-life of nicotine was to help illustrate how difficult it would be to OD by smoking or vaping. Nicotine is metabolized very rapidly in our system. The symptoms you wrote about (increased heart rate, elevated blood pressure, et al) are associated primarily with TOXIC quantities of nicotine. Yes, your pulse goes up a little while you smoke, but not to any harmful degree. Certainly not nearly as much as it does just climbing a flight of stairs. Testing for nicotine is done by measuring cotinine, which is the primary metabolite of nicotine, because nicotine goes through our system so quickly.
Look, most addictions are harmful to a person, I understand that. Alcohol or drug addictions can ruin a person's life. Gambling or even sex can become harmful addictions. If you want to argue that ANY addiction is harmful, well you certainly have a strong point. But what I'm saying is if nicotine, by itself, taken in normally low doses, is in fact "virtually" harmless (like caffeine), then why should we see it as potentially bad for us?