Their argument? "Grocery has been bombarded by a plethora of quality symbols, large and small. The tractor is just another one. It will tick over but never go into top gear." Pretty damning. Yet, a closer read of the Curry report might have set the doubting Thomases thinking.
What Sir Don was doing, of course, was challenging the entire food chain to show the world, and Whitehall in particular, that its self-regulation scheme for food safety was substantial and workable.
And while it was not projected in so many words, canny readers spotted the message that, without full industry commitment, government might wield a heavy hand in matters of safety regulation. And the consequences of that would be unthinkable.
When the NFU unveiled the tractor on Tony Blair's Downing Street doorstep two years ago, the union dreamed that the symbol would pull together the wealth of assurance marks which adorned British produce. Easier said than done.
Hopes were raised when a brace of chiefs from the multiples swiftly voiced support, but it was always going to take bags of hard cash to gain overall trade and consumer acceptance for the logo. And since it did not have pots of money for that purpose, the NFU proceeded largely with persistence, not pounds.
So, it was no surprise to anyone when the Food Standards Agency, in a review of food assurance logos, declared that consumers were unsure what the little red tractor stood for.
But now, in response to Curry, detailed plans to refuel the tractor are being drawn up. Given the vehicle's controversial history, the working paper circulated by the tractor's promoters is clear in its objectives. It wants a "suitable vehicle to meet the requirements and aspirations of retailers, processors, farmers and others in the food chain, that provides a reassurance to consumers of independence, good governance and credibility".
Quite a task, given the industry's record for making public unity pledges and, in practice, often ignoring them. However, to appease some of the doubters, we are told more emphasis will be placed on environmental standards and inspection criteria. But, before that can happen the big challenge is to win agreement from all the food chain to own the scheme rather than confine it to the primary sector. After all, the tractor was not designed to be "driven by producers for producers".
Assured Food Standards, which administers the scheme, says it has had positive talks with the British Retail Consortium. And that suggests that more retail CEOs may be convincing doubters within their buying teams. But given there is still a low public awareness of the logo, perhaps AFS could recruit marketing expertise from relevant parts of the food chain to augment that of the NFU?
Sir Don Curry's hope that the tractor should be a baseline standard that all food produced in the country should attain is an intelligent objective. The problem lies in winning cash support from retailers and manufacturers, plus, of course, the government. Without that, and stronger promotion, the tractor might, ultimately, be destined for the scrapyard. That would be a tragedy for the whole food chain.