That didn't happen yesterday. The vote took three times as long as normal, with no explicit indication of which way senators had voted. Watching it live, it wasn't hard to guess that the reason for the unusual pattern was that Republicans were struggling to come up with enough votes to move the legislation forward, but now we have confirmation:
“After the vote began, it was quickly clear that Republican leaders were struggling to deliver enough votes to clear the 60-vote hurdle upon which they had insisted instead of a simple majority, and a potentially catastrophic default suddenly seemed possible,” Reid spokesman Adam Jentleson told CQ Roll Call in a statement. “At Senate Republicans’ request, the clerk did not call the names during the vote to make it easier for Republican leaders to convince their members to switch their votes.”One issue here is whether or not it was proper for the Senate Republicans to request the silent vote, and whether it was proper for Senate Majority Leader Harry Reid to go along with their request. Transparency seems like the right answer here, but on the other hand I suspect that if a silent vote weren't an option, the wheeling and dealing would have taken place off the Senate floor. I don't, however, think it's likely that they would have allowed a default. So in a way, in this particular case, the partial secrecy may actually have provided more transparency.
But the other issue is that despite months and months of hot air about how they would refuse to raise the debt limit without strings attached, it turns out that the Senate's Republican leaders weren't just bluffing, they were flat-out lying. Not only did they support raising the debt limit, they were willing to twist their colleagues arms to do so, even if it meant humiliating themselves. The strange thing about all this is that for once, the filibuster screwed the GOP, because if senators like Ted Cruz didn't have the ability to demand a supermajority vote to end debate, none of this would have ever happened, and Mitch McConnell and John Cornyn could have happily kept on pretending that they oppose raising the debt limit.