Angel Wing in Geese/Ducks

Yesterday I posted one of these images in a Facebook photo group and was told the goose might have Angel Wing (it also goes by other names). It is a deformity caused by nutritional deficiencies which makes the wings grow outwards rather than to lie flat against their bodies. It can leave them unable to fly making them vulnerable to predators.

I never heard of this, but a lot of it is due to people feeding ducks/geese white bread. Has anyone ever see this type of thing? I'm not 100% sure if this goose has it or if it was simply drying off - since I wasn't aware of Angel Wing, I didn't pay particular attention to this one goose. It was part of a flock floating in the water.

Its something that has been talked about a lot, the Queens Swan-keeper (the Queen sort of owns all the Swans in the UK) has said bread is not a problem, ok better if you feed grains etc,but a few years ago when every one over here stopped feeding bread due to bad press he was finding starving Swans and ducks all over the place in winter because people did not feed them.
I think the answer is if its a bad winter and a shortage of food then feed bread rather than nothing.