I haven't examined it entirely. I view it more as a loyalty vote and a certain number of Republicans would never vote for it, so don't have to worry about whether it is sound.
It's guarenteed to get at least 6 to defeat it. That leaves the other other Republicans free to use the vote as they choose, and I find it interesting which "republicans" choose to vote "no" on what is no more, no less, than a protest vote against the nonsense of the Dems amendment.
To me, it sounds more like a "Oh, you want to make a bill about Rove and other government employees, well here's one that includes you too" kind of thing.