I still have yet to actually read the original "eratta" BS. The link you posted took me to...another of your posts. The link there took me to...an online store page for a Mutants & Masterminds book with DC superheroes on the front.
I've been searching the boards linked to that store and the closest I can find is a "quote" with that exact information. Now, the quote doesn't link anywhere, nor does it credit anyone (other than "saved blog post") in its tag.
So, until you can find an actual link, I'll treat this as some BS your DM or some other idiot made up.
The link is old, and takes you to archives. I've searched the archives, but the post was old, and taken off. The problem with PF forums is that they can only hold so many topics before they're removed.
If you don't want to believe what I found, that's up to you. I was the one who originally found it and brought it here. Both of my DMs know of it, but only after I told the second one about it after he started whining that ToB was too powerful and he shouldn't have allowed it in the first place.
If you can, get a hold of Rich Baker. He's the one that was contacted about it. Much like Mike Mearls on the updated Hexblade. (I PMed Richard myself about it. I'm just waiting on an answer.)
Favored Power Attack >>> Imp. Favored Enemy
Double power attack damage vs. +3 damage: Which one sounds better to you?
Could always take both. The Improved basically covered whether he was using bows or melee.