Hey Kap:
I've smoked in fits and starts for over thirty years....10 years on, 10 years off, 10 back on, quit for 8 months last year but started back again this past winter.
I can tell you without a doubt that my voice is hugely impacted by smoking.
The more I smoke, the lower my range for sure, but the high end is gone as well as the ability to sustain a note.
I can also tell you that some of my sickest and most miserable times have come in conjunction with quitting...the nausea, dizziness and just plain confusion caused by the withdrawal were unbeleivable last time.
BUT
Most of those symptoms passed within a month (anyone who tells you they pass after a few days is blowing sunshine up your skirts) and I found I could breathe easier within days and the raunchy throat also cleared up quickly.
Add to the health benefits the fact that I was saving about $50 - $60 a week not buying smokes and you can see where I'm going.
I've only been smoking again for 6 months and it's as if I had never quit. The phlegm, wheezing and dependance are back full strength and yes, I do a better job at Johnny Cash again, but Slim Whitman's out of the question.
Time for me to take another run at it and good luck to both of us!