Why I Hate the "Turning Friends into Lovers Demeans Their Friendship" Thing

I delayed a long time before posting this, because it had its genesis as a shipper-war rant (and my HP-trained instincts to start shipper wars-to-the-knife over my OTPs do not need encouragement), but recent events in my fandom have reminded me all over again why this argument pisses me off.

( By popular demand (as in, two people asked about it) )