What to do with quite substantial edits in the review queue?

Question

It happens sometimes that someone, frequently a new user, proposes a quite substantial addition to an answer. This addition can be a longer explanation of a term used by the answerer, a longer description of a software, etc. At the moment of writing, there is a proposed edit for this answer, with a longer explanation of the word sic.

Though in principle correct, I find these additions a bit too invasive with respect to the original post, especially in the case of a highly-voted one, and I'm frequently undecided on what to do (I sometimes skip the review).

Hence, the question: what to do with this kind of edits? Do we have a general, even implicit, policy on this?

Answer 1

I generally allow those edits to go through, as long as they are simply expanding on the original idea of the answer. The case you posted is a fine example; the original poster suggested something, but the edit provided a more thorough definition and a few examples of usage. To me, that's a fantastic edit, which expands on the original answer and adds significant value.

However, if the edit either (a) changes the answer in any way or (b) adds unrelated information, I typically reject using one of the canned reasons.