I find his comments typical of former Patriots. I would have to think that even with Jacoby the Colts would win more games than that since he got most of the 1st team snaps in OTAs. With a totally functioning Andrew Luck, that number is just plain silly.
You're right, he's not an all-star. But Breeland is easily the best zone corner available. Good enough to command a contract of 3/24 when he was thought to be healthy. And he was ranked as a top-40 free agent on every reputable top-100 free agent list. NFL.com, PFF and ESPN.com.
So, he may be average, or slightly above average, but no one here is sure that we have any one better. Someone from our collection of unknowns may wind up being that, but no one knows for sure. We're all guessing. I'd be very happy to have him signed, especially since Wilson apparently didn't play much this spring due to some unknown minor injury.
I don't see a downside to signing Breeland with a decent chance for a good upside. You don't often get a chance to sign someone of his ability to a bargain contract. I'd take it.