How good or bad the move of promoting Swanson was depends on the yardstick you're measuring by. If you're looking at it through sabermetrics or through the eye of a professional scout wanting to do what's best for a team's on the field chances long term, it was a bad move.
If you're a businessman looking to maximize a player's value to your business enterprise by teaming up the marketing opportunities he offers with the very rare chance to open a new ballpark, then the move was pretty fantastic.
Promoting Swanson was a terrible baseball move but a savvy business move. Usually a good baseball decision is a good business decision because putting a good team on the field is good for business. But when the two don't align, business wins every time. That's true with every GM.