I haven't had a ton of experience smoking cigars yet having just started up semi-consistently this year but I do have a lot of experience in my limited experience with cigars burning unevenly.
Being a perfectionist, it frustrates me too, just as a new skiier wants to 'look good' coming down the slopes. It makes me feel better when I'm holding a nice, evenly burnt cigar just as it does when I know my turns and form shooshing down a snowhill are awesome. An unevenly burnt cigar is ugly with its jagged, ragged foot, not to mention that the taste delivered to your mouth is, from what I've read, not ideal, not the intended flavor of the cigar because the flavor delivery won't be consistent and even as your roller has invested so much time for your pleasure.
But then I began to realize, hey, I'm relaxing, chatting with good people (most often including my wife) and having a nice drink of red wine or an appropriate cocktail and if the worst thing I have to deal with is an uneven burn, then life's not so bad.
And the more I'ved smoked, I began to realize that a) uneven burn happens a lot and b) you can absolutely correct it, and should. Heck, I had one of the most frustrating uneven burns last night while smoking a Tatuaje Reserva J21.
About 10 minutes in, I was developing the nice, deep, C-shaped wrapper/binder blunder I feared and loathed so much. And my humidor was spot on in temp & humidity (thanks to a recently purchased temp/humidity guage) so I don't think it was a humidity issue. Maybe it was a sloppily constructed cigar but I've heard mostly good things about the J21 and of course, I have begun to really like Tatuaje for producing some great sticks.
I don't think it was the way I lit the cigar because I think I've really perfected that. I warm the foot first by rolling the cigar close (but not in) the flame. Then I take it away from the flame, blow on the end to get the embers going. Then I put it in my mouth and touch flame to cigar and roll & puff a few times to get it going evenly. Then I check the foot again & blow on it one more time.
Not only did I have to correct the J21's uneven burn several times (by igniting the unburnt wrapper & lining up wrapper & binder evenly again and carefully & lightly rubbing the ash off to get even again) but the sucker went out on me a few times too. Both when correcting an uneven burn & when relighting, I like to blow through the cigar (like a straw) to expel any of the residual smoke (either the stale stuff that's left when the cigar goes out on you or the flavor of unevenly smoked tobacco).
What I've been told when something like this happens, either the cigar burns unevenly or goes out, and you've ruled out humidity issues (because of course, if the stick is wet, it's gonna be tough to smoke), the culprit very well could be a plug.
Another fact of cigar life is that plugs exist. A friend of mine likes to feel up his cigar before lighting (and in fact, before that when you're in the store buying...another reason why it's good to go to your B&M instead of buying online). He turns the cigar over in his hands and firmly (yet carefully) presses along its length to feel for 'firm' spots. Of course, you have to be sure that your B&M won't have a problem as you manhandle his stock. As my friend explained, a good, properly rolled & stored cigar should not be hard as a rock and certainly shouldn't have unevenness and 'rocky spots' as you press down the length. The cigar should be somewhat supple, not soggy, and slightly spongy but not too much so.
This 'touch-test' isn't foolproof. It's not going to remove plugs from your life. But as long as you're equipped with the tools and information to deal with them, you're solid. And as I've learned to get over being ashamed of my uneven cigar, it bothers me less and less that I have to take matters into my own hands and correct the bastard.:ss
