"I completely understand and can attest that just one hit is not ok."
Nicotine addiction is a one trick pony in that it only cares about one single thing: the next fix. The Addict starts to atrophy the moment its most recent fix is finished. Nicotine has an elimination half-life of about two hours, so once the two hours is up The Addict springs into action. Fidgeting, anxiety, irritability, restlessness, constant thoughts: I can have a dip on my way to the next meeting; I can have a dip if I mow the lawn; I can have a dip if I run out to Home Depot because we "need" to fix that loose handle. The longer The Addict is denied nicotine the weaker he becomes... but he becomes as strong as EVER the very moment he gets Just One.
Unfortunately, The Addict is also You. You share a brain which makes it challenging for the unprepared to recognize the bullshit justification of why Just One is okay. You might tell yourself that now is too stressful a time, that quitting when the wife is away would be easier, that you'll quit on the 1st of next month, next year... You might tell yourself that you've earned Just One, or maybe that you finally got it under control and that now you know that you can have Just One because you've proven that you can quit. You might even tell yourself that you're better, stronger, smarter, etc. than all those internet weirdos on KTC. THESE are the warning signs you need to be wary of! When you hear those thoughts rattling around in your head, smack yourself in the face and get in touch with a Quitter. Recognize the lies, reject them, and keep putting The Addict in the sleeper hold of a lifetime. You will have these battles every day. At first they will be frequent and fierce, then they will be occasional and manageable. One day they will even make you laugh and marvel at the fact that you STILL have those thoughts even after hundreds of days, but you'll squash them in an unfair fight like Mike Tyson in his prime vs Justin Bieber.
Quitting nicotine is about winning the Just One battle. Just One is not only not okay, it's your biggest enemy.