Is it best to remove sausage casing before cooking sausages or not? I don't see it mentioned in recipes, but have seen it done by people when cooking. Is this a matter of preference or is there any improvement to quality of flavor when casings are removed?
I'm sure it's a personal preference.
Personally, I'd never dream of doing it, unless it was for a dish that specifically called for it, or one that requires 'chunks'*. Part of the job of the casing is to keep the sausages moist. You shouldn't even prick them with a fork whilst frying [yet some people do].
For chunks, there's a distinct difference between frying them whole & cutting up than cutting then frying. The first retains the shape, the second tends to squeeze out of the ends as the casing shrinks.