Whether Shapiro and Antonetti have been successful really depends upon how you measure that success, doesn't it? If the yardstick is Division, AL or World Series titles then they are certainly failures.
But, if that yardstick is exchanged for a calculator and checkbook, then it's quite possible that they have continually made money for the Dolans. Forbes and other sources have regularly claimed that the Cleveland Indians franchise operates in the black. Dolans have denied that, but Forbes has never retracted its stories and they continue to make the claim.
As the sales of other franchises in recent years have shown, the real value for MLB clubs today is in the cable networks they control. Baseball and the fluff programing created around it (golf shows, baseball and other sport talk shows, high school sports, etc.) is cheap programing. And, unlike some teams, the Indians really don't benefit much from their deal with STO because the Tribe has no ownership interest in STO: it's owned by Channel 3's owners and....yep.... the Dolans.
BTW, ever notice the Time-Warner Bleachers at Progressive Field? Ever notice that the Tribe never announced how much (if anything?) Time-Warner paid for that deal. But, I wonder whether that deal had any relationship to STO's deal to be carried on Time-Warner? Similarly, ever notice that Channel 3 gets to provide the scoreboard news and weather updates during games....and "sponsor" the weather seminars at the park for school kids and such? Does the Tribe really get much benefit from this stuff?
So, IF the Dolans want to reduce their financial risk and continue to milk the cash cow of MLB, then Shapiro and Antonetti might be exactly the ones they want running the club. They squeeze the nickles and pennies (and fans), churn the roster with low cost options and, once and a while, get lucky with a trade (like Choo or Chris Perez) and minor free agent signing (like Blake) so that the team competes enough to keep the minimum needed fan base interested.
Sadly, if most of the above is correct, there's really not a lot of hope of seeing another sell out streak or World Series championship parade in Cleveland anytime soon....:(