I hope this goes to the author of the post as well.

I'm sorry, I misunderstood, I thought that by saying an OC shouldn't upstage a canon character's role that you meant an OC should never be a main character in a fic. It didn't occur to me that you meant they should not take the place of a canon character. Sorry about that. I totally agree with you that if you're going to have an OC you should make him/her their own person, not just use them as an excuse to make another Harry, only without all of the pesky canon restrictions on who Harry is.

Also, mind linking me to some of your fics? It's so hard to find good OC centric fics....