the roach holds more rezin then any other part of the joint the reason it is so harsh is because your putting fire to smoke that got stuck to the weed on the way through the joint n turned back into a solid form from gasious thats also why the end burns hotter n it can also poop rezin out the end all over ur lips/hands BTW IMO a joint isnt allot to smoke by urself ive sat there n smoked 1/4oz blunts by myself before