Last time I saw them I had the feeling he had not much breath left at the end of a lot of sentences singing. He sounded not like he smoked/drank for years, but also like someone was squeezing his throat.
I stopped myself some 8 years ago after years of heavy smoking and have a lot more breath now. I lost my father earlier this year because his lungcancer spread towards his brains. (This is not a nice way to die I can tell you.) I think you can imagine what I think about smoking...... ;-)