Is it appropriate to Edit an answer just to improve the answer-er?

Question

Regarding this little gem from a 19k user:

@Jon instead of improving your answer I decided to write my own. – Philipp Apr 27 at 11:43

And this question: Editing the pixels of a rendered image

I left a comment stating that he should expand his answer.
I'm wondering if it's also appropriate to suggest an edit to his answer, like so:

[EXPAND: Does BlendState matter?]

I know that it does, and the answerer probably does to, but it was omitted in lieu of a one-liner and youtube tutorial link.

I don't want to be like Philipp; I want to help the user improve his own answer. When Philipp suggested that I expand on my answer, I didn't even know there was another way to do it; I needed Philipp's knowledge as much as the OP. If he had taken the time to list all 2 of the methods, I would have realized that I was out of my depth, asked him to post an answer that I could up-vote, and removed mine, if he agreed.

Answer 1

Regarding this little gem from a 19k user:

There is nothing wrong with adding one's own answer to a question rather than improve an existing one and users are under no obligation to favor improvement over new posts, for a variety of reasons. There's nothing eyebrow-raising whatsoever in Philipp's decision.

I left a comment stating that he should expand his answer.

This is good (although it might be considered bad form by some to explicitly "bribe" a user with votes in exchange for improvement, as you did in your original comment).

I'm wondering if it's also appropriate to suggest an edit to his answer, like so:

No, it isn't. Edit an answer to improve it, not to embed commentary within it that it should be improved. That's what comments are for. Editing to improve answers should not fundamentally change or add significant content to (non-wiki) answers.

If you've got an edit in mind that adds a lot of content, it probably is better off as a new answer.

I know that it does, and the answerer probably does to, but it was omitted in lieu of a one-liner and youtube tutorial link.

One-liner tutorial links are the definition of "link only" answers and should be actively discouraged/voted-down/voted-for-deletion.