The survey is here:

The survey sample is comprised of 66 participants: 43 former clerks of current Supreme Court justices, and 23 attorneys who have argued before the Court.
The survey was distributed to 398 former Clerks and 239 attorneys who have argued before the Court. All of those in the sample were contacted first via e-mail, and ere then reached by phone at least once to encourage participation. We provided two follow-up e-mails as additional encouragement to participate. The survey was administered online.
Of the Supreme Court clerks, 12 clerked for the “left” block of the Court (Justices Breyer, Ginsburg, Kagan, Sotomayor), 21 clerked for the “right” block of the Court (Justices Alito, Roberts, Scalia, Thomas), and 10 clerked for Justice Kennedy. Given the tenures of the various members of the Court blocks, this is a representative division of the populations of former clerks.

Let’s say how they fare against the crowds.