I think this comment is spot on. Perhaps one way to correct against this bias would be to "backtest" the principles in question on other successful investment managers (at the least)? Of course, the difficulty there is that usually you only have imperfect information about how a firm is actually run.
I agree that some sort of back test is necessary to evaluate the strength of his arguments. I am not sure what this back test would look like. Presumably some sort of case study of companies (both successful and not) that apply some or all of these principles. Data collection and validation would be a bitch. Curious if this is commonly done in academic research, possibly sociology or economics (of a behavioral flavor).
