It can't mean they're saying "we must protect this asset for the future"?
It can mean that too. They don't care about making the playoffs because they're shutting down Strasburg in September in order to protect that asset for the future.
No matter how you cut it, shutting down Strasburg is essentially them punting the playoffs.
What will be really interesting is if they shut him down for the season and they DO make the playoffs, will they let him pitch in them?
