that stubborn husk causes death in nature. I see nothing wrong with helping a poor bean out if it's having trouble. I had two beans do this to me, the first I let go too long and it ended up deforming the first leave pretty badly. The second husk was firmly wrapped around my second plant so I slit it open and out popped a full leave all crinkled up inside like a party favor or something. I was really shocked as I am certain the plant would have died without my help. I bet most people help their beans when they start to struggle like that.