There is zero reason to not expect this team to get to the Super Bowl. Nothing stands in their way.
While Mack is the most underrated RB in the NFL, A Top-7 Back in production (when healthy), it's always good to have someone share the load while helping to take the pressure off of Luck by respecting the run.
From Rotoworld with Rotoworld comments:
Colts signed RB D'Onta Foreman, formerly of the Texans.
Backup RB Keith Ford was waived in a corresponding move. Recently waived by the Texans himself, Foreman lands in a loaded backfield as the likely early-down backup to Marlon Mack. Nyheim Hines, Jordan Wilkins, and Jonathan Williams round out the rest of the roster, with Spencer Ware likely seeking out an injury settlement to play elsewhere. It's worth noting longtime beat reporter John McClain of the Houston Chronicle believes the Texans waived Foreman because they were unsatisfied with his "work habits" — something that obviously won't stand in Indy. If Mack is dealt another season of nagging ailments, though, it's Foreman who'll be a name to monitor as the power-running successor (despite his ongoing Achilles recovery). In the meantime, Mack remains an unequivocal RB2 across all formats.
SOURCE: Aaron Wilson on Twitter