Add TypePolicy.merge to the cache documentation?

I was reading the InMemoryCache documentation about the TypePolicy options, and I see it is missing the merge property. Should this be added to the docs, or is it hidden by design? I’d create a PR, but I have no idea how to describe it.

As an aside, I used it to get rid of the warning about not being able to merge some types. In my case, these are child objects without their own identity. I found a StackOverflow answer saying to set merge to true which solved the problem. However, now that I’ve read the docs more fully, I see the actual solution is to pass false for keyFields so these objects get embedded in their parent. But merge is clearly used by the cache, so I feel it should be documented.

cache: new InMemoryCache({
  typePolicies: {
    Address: {
      merge: true,              <-- document this?
      // keyFields: false,      <-- better in my case