to add or not add; that is the question

The following does not seem to me an atypical statement in related topics:

CRCs are so called because the check (data verification) value is a redundancy (it expands the message without adding information) and the algorithm is based on cyclic codes.  [emphasis mine]

To the ones who talk about "adding information," this is not a meaningless distinction.  There are some functions of a collection of bits that may be considered strictly as functions of those bits and other functions that compute a function of  those bits with some other data built-in to the function itself.

So why, when it comes to biology, do some people pretend statements about conservation of information are meaningless?