This is a Hoboken Peruvian Torp. This picture shows what it looks like when a cigar starts tunneling. When smoking a cigar that tunnels you will notice that the cigar is burning hot, you will feel the warmth as you draw. You will also notice a significant reduction in the amount of smoke with each draw. If you look at the ash you should see something like what is pictured above.

So... are you making a comment about the cause and prevention?

I saw your other picture, with a comment about clipping.

I am interested, as I sometimes have this problem, and am assuming it is due to outer part of the cigar being at a higher humidity than the inner, because it has not had time to equilibriate where ever it is resting.