I don't get a heavy buzz unless I take a LOT of drags in a fairly short period of time. That buzz could be coming from increased oxygen intake though.
On the other hand, I know that I'm getting nicotine in my bloodstream. I can feel it. The expected effects are there, it's just that they come on far slower. I still get the calming effect and I stop craving the smoke/vapor after ten minutes or so.
Obviously it's going to be different for different people. I was a 1/2 pack a day smoker of Camel Lights, so my natural nicotine intake level was pretty low. T-Bob was a heavy smoker, so it's likely that he simply can't get enough nicotine out of the vapor to break through his increased tolerance to the drug.
Plus, he's absolutely right that there's "something missing" from e-cigarettes. I wasn't addicted to cigarettes, I was addicted to CAMELS. No other brand would do it for me in the same way. That's due to additives, no doubt. And that's why the new tobacco legislation is good in some ways. It requires manufacturers to state the ingredients. We need to know what it is we're being addicted to, because it isn't just nicotine.