I often get the slight acetaldehyde flavour from black ipa both commercial and homebrew, but it's not unpleasant at all in this style for me. I'm not sure if it's actually a flaw in the beer, or whether the clash (good or bad) of flavours from the hops and debittered roast can give off this type of flavour or not. Anyone any thoughts?
Not sure why but it should not be in the final beer taste. As you know it is a part of young beer that gets cleaned up. It also can come from too much oxygen getting into the finished beer.