The very short version is........you can seal Char Cloth in straws and it works great. If you want to see some Simple testing, read on. I was going to seal some Petroleum Jelly/ Cotton in some straws to replaced what I had used. I saw some char cloth and decided to seal some in the straws and see how it fared? Had some scraps left over and sealed them up, put them in water with a rock on top. Left it for 35 mins, unless you are a Navy SEAL, that is longer than most of us can hold our breath. So I figured that was long enough. Got some Cedar for a tinder bundle. Cut open the Straw, I will say that at this point it will come out more like dust and chunks. Not really Cloth anymore. I used the Junglas to start this, with the longer spine it provides more Runway to get a spark. Rocks I used were found out on the trail where I hike. No real take away here except I now "Know" that it will work. I always carry a short piece of Hacksaw Blade and a small package of char cloth in my wallet. This will be a way to carry some water-proof Char Cloth in places where I toss them. Pic of the Kits they will be put into. That is all, carry on................
I will say that I was slow on the Uptake as far as sealed straws go. While up-dating my kit I found that they work great for Fishhooks, Swivels, Lead BB Weights. Salt and spices. I just went for a quick walk and did a quick test. The area where I hike. Sagebrush tinder abounds, it equals Cedar, Inner Cottonwood and a few others, as a favorite of mine. Found a rock and got the Hacksaw Blade out of the Kit. Banged out a Coal. And the finished product.
Just to add, I live about an 1 Hour from the cascade Mtns. And there are some great Bow-drill woods up there, Cedar,Willow,Aspen, Alder and on and on. But for me, if I am thinking long term "Circle of Fire" it will always be some type of Flint and Steel. I can grind out a Bow-drill Fire to get the ball rolling but after that............... I will be banging on one of my Esee knives with a Rock for my fires. Where I am at, Charring natural materials like Cedar, Sagebrush Bark ect. will give me unlimited Char. The reason I carry a knife made from 1095 is just because I can sharpen it on a rock, or start a Fire with a Rock. For me and mine............That will be an ESEE.
By the way, you can Char material in a Aluminum ESEE Tin. Just throw in some punk wood or what ever you like, get afire going on top. After it has burned a bit, put the lid on to snuff it out. { see above picture} The ESEE tin is my favorite All in One survival tin as it will hold a two person SOL Survival blanket and the rest of my gear, Great tin! Here is a shot of the smaller kit with a high-light around the fishing gear sealed in straws. And finally here is a shot of someone having a really bad day. Probably worse than yours..............