Because no matter how much I thought about it, I couldn't find a way in which the comment was a useful contribution to the site; rather, it seemed to be spam no matter which perspective I tried to view it in.

Crosslinking is potentially valuable - announcing that something from here has been crosslinked by you is not. If there's some important response elsewhere to a post made here, that is notable and worthy. Stating that you're trying to provoke such a response isn't.