Fifth Circuit pondering "irrebuttable imputation of all confidences" for laterals?

News stories here and here suggest that the Fifth Circuit is deciding whether there is an irrebuttable presumption that a departing lawyer gained all of his prior firm's confidences.  There's only one sane way to rule on that issue. I know that the federal appellate courts rarely get DQ issues these days, and I've heard the conventional wisdom that fewer and fewer federal judges have a deep understanding of private legal practice, so I hope that the Fifth Circuit has the resources to understand what's at issue here.