Prof. Dorf makes the implausible claim that law schools train lawyers to think about what their clients morally should do as well as what they legally can do: "As for legal education, the whole point of the Socratic method is to bring out the moral and policy consequences of various rules of law, so that, to the extent permitted by authoritative sources, one can select the best rule under the circumstances." Having taken one of Prof. Dorf's exams, if he was expecting answers that considered explicitly moral consequences of various rules of law, I at least can console myself that my mediocre grade was due to a failure to meet that expectation rather than a general lack of Fed Courts understanding. Certainly my other professors never have indicated that they wanted us to discuss what the client morally ought to do. I'm not even sure how to apply that to something like my tax classes -- on an individual basis, presumably one morally ought to pay lots of tax and support the government, but on a corporate basis, one's obligation is to shareholders and thus to corporate tax minimization so the money can be passed on to shareholders who then as individuals can pay lots of tax.
Professional Responsibility is our ethics class, but it essentially comes down to 1) not intermingling with the client unless we tap that ass before it is client ass; and 2) steering between the Scylla of the bar and the Charybdis of government subpoena when it comes to disclosing privileged information. Telling our client the moral course and refusing to tell him what are the other options, which though less moral are still legal, is a good way to get into trouble for bad practice of law, just as nowadays doctors aren't supposed to act paternalistically in presenting only the treatment they think you should pursue.
A more interesting point is raised in the comments. Jamison Colburn says, "I do, however, recall a colleague who teaches ethics and methods suggesting at the time that the torture memos were a category mistake: they were packaged as an unvarnished presentation of the law when, in fact, they were an exercise in subtle twisting usually reserved for appellate papers." For any reader who hasn't gone through legal research and writing, there are two main types of writing law students are taught. The first is the memo, which is supposed to be "an unvarnished presentation of the law." The underpaid and underappreciated LRW teacher hands out a hypothetical case and we research and write a memo that evaluates the client's chances in court. It is not supposed to be biased in favor of the client, because that would be completely useless; the client -- and if working contingency, the firm -- wants to know whether this case is worth pursuing. The second is the brief, in which even a supposedly neutral portion like the Statement of Facts is presented to emphasize those facts that favor one's client and disfavor the opposition (like their saying her mastectomy was a "boob job"). This is literally a somewhat academic distinction; in practice, what gets the catchall label "memo" slapped on it may have been requested as, "How can we structure this transaction to minimize exposure to regulation?"
If Bush asked for a dispassionate assessment of the legal arguments for and against his intended treatment of detainees, he was poorly served by the work produced by Messrs. Yoo and Bybee. If, as I find more likely in Bush, he asked for them to figure out the best arguments to give their client the broadest possible scope for action, then they delivered.