But when you set out to do that you first have to make sure they really are identical, and since everything from indentation to names often differ it might not

But when you set out to do that you first have to make sure they really are identical, and since everything from indentation to names often differ it might not be so automatic. And then you do find differences, and you have to figure out if they are there by accident because someone forgot to implement a fix or a change in some places or if the differences are intentional. On the other hand, if you realise your abstraction was bad, duplicating a function is always trivial.