That's true, and always worth pointing out. I'm not sure it changes my sense that it's a poor strategy for Democrats, however. It's still the case that any Republican afraid of being tarred as an opponent of closing the donut hole can be so attacked just from the final repeal vote; I'm not sure why we should expect Republican Senators to be more scared of the series of individual votes than the one big one, in this context.
Which gets back to Ezra Klein's original speculation that no Member of Congress ever really loses a seat over that kind of vote, or even that such manufactured votes ever become major campaign issues. Against that, Pump offers the case of Bart Stupak:
[A]fter his compromise became “The Stupak Amendment” that managed the unenviable task of pissing off both liberals (for restricting abortion access) and conservatives (for seemingly “caving” on his pro-life stance), his district became a flash point in the national debate that it wouldn’t have been had he not played such an important role in the controversial compromise. This meets the semi-embarrassing vote criteria in Klein’s challenge because Republicans were threatening an abortion provision in the motion to recommit.If we're willing to accept the idea that the abortion issue in ACA was essentially manufactured in order to generate tough votes for pro-life Democrats, which I don't know that everyone would grant, but I probably would...still, c'mon. If the counter-example is the guy who put his name on the compromise to the extremely volatile abortion issue on an extremely high-visibility issue...well, my guess is that if that's all you have, then Members can feel pretty safe just plain voting for lower-visibility amendments on lower-visibility issues (and, yes, I think it's highly unlikely that ACA repeal '11 will be as visible as ACA passage '10, much less that symbolic amendment votes on the entirely symbolic ACA repeal vote will be high salience in the next election cycle).
At any rate, what kind of tough votes would matter? Two kinds, I should think. One would be a vote that asks a Member who plans to vote for final passage to commit to something controversial in addition to whatever she already would be on record for with the final passage vote. The other would be an amendment that appears to be popular for a Member who supports the bill, but would undermine the underlying bill in some way if it passed. In this case, I don't think that either applies. Nothing can really undermine the repeal bill, because everyone knows it isn't going anywhere, so who cares if amendments pass that render it hypothetically unworkable public policy?
So: if the Democrats go ahead with this, as apparently they may do, I agree that Republicans will be more afraid of the consequences of their votes than is warranted by any evidence of how elections really work. I'm just not sure how Democrats can use it to their advantage.