The latest tactic to nail him, dreamed up by the Chancellor of the Exchequer and RBS's new chairman, is to ask an independent auditor to prove that the company's sport sponsorships under Sir Fred's guiding hand were not in the interests of shareholders.
I am no big fan of the man, but this ploy is as desperate as it is doomed. The time for shareholders to express concerns about reckless marketing behaviour - or anything else they dislike - is at the annual general meeting, not as part of a retrospective bandwagon of disapproval.
God help us if other shareholder groups set out to offset their losses by making marketing directors or agencies liable for historic initiatives that missed the bullseye.
Sure, advertisers must take all possible care to make high-quality marketing investments. But despite the tacit assumptions of procurement scientists, media, advertising and sponsorship are not pure maths. Before the event, the company must do its homework, understand the investment, and know what outputs it expects ... but then embrace the risk.
Reward and Risk are a banded pack. You can't have one without the other, especially in creative pursuits. So any audit of marketing decisions using the handy telescope of 20/20 hindsight will floodlight the uncertainties and so excite more journalistic tutting, but will not prove points about financial irresponsibility.
In normal times, it is excellent for the world's biggest companies to get behind major sporting activities. The RBS rosta of rugby, tennis, Formula 1, cricket, golf and baseball seems to pretty much cover the planet.
Special relationships with Andy Murray, Zara Phillips and Sir Fred's boyhood heroes, Jack Nicklaus and Jackie Stewart, will provoke the most angst, especially as the beneficiaries are now cancelling their own deals. But as Murray points out, the bank has supported his career since he was 13. Not so terrible.
The independent auditor will no doubt accuse the bank's senior staff of buying themselves ringside seats at the world's greatest sporting contests. But even the most venomous opponents of Sir Fred will dredge up little or no actionable material from this inquiry. They should not bother.
Richard Eyre is a media pluralist, email@example.com