Yep, you cut down...so after that, you'll go down to the 7mg....and a few days of withdrawal isn't as bad at 7 as it is at 14 Mg's....
You are still gonna go through the withdrawal, and you are still gonna wanna smoke, and you are still gonna wanna throttle people and leap out of your skin. But the rationale behind them is two fold: 1) gently adjust the drop - if withdrawal isn't as bad as going cold turkey, you are more likely to endure it. Same idea behind giving suboxone to junkies....2) it gives you some practice as 'living as a non-smoker' - hopefully after a few weeks you aren't used to having a smoke in your hand, with your morning coffee etc...
Smoking is 16 times harder to quit than Heroin (and 17 times harder than that for women*) - - people quit heroin everyday. So whatever it takes....do....
(15, 10 and 5?, wow, You guys have a 'top end' that isn't high enough IMO, but I do wish we had a bottom end that was lower)