Well, if you cut into a dread, every hair is cut. All the hairs are very tightly bound together, and zigzagging chaotically. So cutting just a quarter inch into it your cutting through pretty much every hair. It would become wispy, and probably lose quite a few hairs.
I would only consider that if they were really huge annoying or uncomfortable.
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My new book Ban The Taboo Vol 1
updated by @soaring-eagle: 07/25/15 06:05:00PM