That can work for punctures. The back-country that I go to regularly has granite rocks that can sometimes have a sharp edge. The particular tire I was changin

That can work for punctures. The back-country that I go to regularly has granite rocks that can sometimes have a sharp edge. The particular tire I was changing was a 4-steel-ply contractor-grade truck tire, two weeks old, that somehow got cross-wise of a piece of split granite that put a 3 inch gash in it. Goop will not do it in that case. I am still amazed at the damage that rock did. But hey, that's life in the mountains.