I understand, kind of, what the Nationals are doing. They made this plan in the off-season, at a time when very few people expected them to really contend. And, hey, if your team is hovering in third place, around .500 then I don't see what the big deal is. Why risk him getting hurt? What do you have to lose?
Flas forward to now. The Nats have the best record in the NL, and their rotation is really strong all the way around. Edwin Jackson is probably their worst pitcher, and he has an ERA+ of 112 (to contrast, the Sox only have three starters with an ERA+ over 100). It's unlikely that they'll collapse to the point that they'll miss out on the playoffs entirely. Will the 5 games he'll miss in September kill them? Probably not.
But in a short series, pitching is crucial. We of all people should all be intimate with that from 2005. Are their other 4 pitchers good enough to take them through the postseason? Probably. But given how difficult it can be to return to the playoffs - as people have said, who knows who else could get injured or have an off-year in 2013 - it makes so little sense to sit their best pitcher. It's not like he's going to be called upon to pitch another hundred innings. The most he's likely to pitch is 4, maybe 5 games. Somewhere in the neighborhood of 30 innings. Seems like it's contrary to the very nature of sports itself to handicap yourself in the postseason.
What happens if the Nats make the World Series and lose in 7? Will people say, "Everybody knows that the White Sox wouldn't have won if they'd had to face Strasburg a couple times"? It's a mockery of the sport.
I kind of respect the Nationals for making their plan and sticking to it no matter what. But I'd respect them more for showing some more respect for the game.