I hate retractable leashes too, but only when used by nitwits like the people Barking encountered. They do have their good points if used properly and responsibly. Gee, just like a lot of things. It's too bad when the poor users spoil it for the good ones.
Oh yeah, I've seen them cut. My neighbour got a very bad gash behind her knee from her own dog which she allowed to roam to the end of the leash and he wrapped it around her leg. Could have happened with any one inch wide nylon leash I guess but the extra length gave her dog more momentum and he really tangled her up too. And some of the darn things are like a narrow clothesline wire in size, those can really cut.