It's true, this stuff is superior to anything as far as removing soot from my wood stove glass.
Just spray it on the inside of the cool glass and wipe all the black stuff off.
Very nice before company comes over because it is so fast and the glass is so clear - it looks like it's not there...
I have always been a little apprehensive about getting on my hands and on anything else. One time got a little sloppy and did drip a little on tile hearth and hand but I washed it off and did not suffer any ill effects.