If you still are harboring hope for this guy, you're not thinking things through.
The hype was born out of an interesting back story, really. Ability? Yeah, sure. A bunch of WRs with ability just got cut. And a bunch of WRs with no "upside" just made rosters, including Griff Whalen and Vincent Brown. He couldn't beat out Vincent Brown. He's a year out of college, and couldn't beat out Vincent Brown. The depth of the Colts WR core isn't a problem for Duron Carter. it's a problem for Griff Whalen! Because of the talent in front of him, Griff won't get many targets, or fantasy opportunity. The problem for Duron Carter is that Griff Whalen and Vincent Brown are keeping him off the team.
Was Indy the easiest rotation to crack? No. Could he have made the Panthers or Browns? Maybe. But how can anyone claim a guy has any upside when the thinking has to be, "Man, I hope he goes to the worst group of WRs in the league, so he can maybe get a job..."
It's really dangerous to not step back and re-evaluate these guys. Carter may not have cost you a lot, but he's costing you a roster spot every day. Every team has a young guy that made the team, kind of out of nowhere, and you could have one of those guys on your team.
He needs to be treated like any other UDFA flyer you took, hoping to catch lightning in a bottle. You give him a chance to flash, and if he doesn't, you look around for the next sleeper.