Alas, Cohen's lawyer is a complete retard
“Any competent atty would have refused...”
Even non-attorney Susan McDougal knew she could not be forced to speak and suffered the consequences. Many big city, politically connected white-shoe lawyers like to talk big then go home to drink and sleep; won’t go to jail for a client, and especially not go to jail defending the attorney-client privilege. You are right, the argument should have been to demand her recusal first. Then the judge’s demand to reveal clients’ identities without the government first proving that the seized documents with the unnamed client was relevant to the (un)constitutional seizure, the judge’s order to disclose was premature at best and there was no legal urgency for such disclosure.