These situations could not be more different. Lannan is PHYSICALLY able to pitch, he is still pitching now. Strasburg gets injured (God forbid) and can no longer pitch his career is OVER.
What business decisions baseball teams make based on a players ability and situation is completely different than knowingly putting them at physical risk.
I understand what you're trying to say, but honestly this is a nonsensical comparison.
Letting a pitcher take the mound, period, is putting him at physical risk.
