A few weeks ago, I mixed several batches of my own e-liquid in different flavors with zero nicotine. What I noticed was the lack of TH and I found myself vaping constantly. What I have found that works for me is to have two PV's, one with nic and the other without, and I use the zero nic one until I get a craving for nic and then switch for a while. Seems to work well for me. Eventually I'd like to get to a lower nic level than 28 which is what I have been using. Maybe down to 9 or so, and then stay there.