I had a plastic bag ambush predator pounce on my chain, wrap itself around my cassette and lock up my wheel, forcing an unplanned skid and knackering the rear mech in the process as it ungracefully tried to pass round the jockey wheels.
Luckily, however, inside the remains of the bag were a couple of mostly unscathed napkins so I could wipe my fingers after extracting shredded plastic from my cassette, so it wasn't all bad. Some bags may be feral but some of them still have a modicum of consideration for other road users.
^^^HA! True story, Von Fiction?
Probably not, cos a bag locked cassette won't cause the freewheel to stop
Probably not, cos a bag locked cassette won't cause the freewheel to stop