How many barleycorn in a giant slipper?

On Thursday this week you, as I, may have awoken to giant slipper news. The story, that Tom Boddingham ordered a size 14.5 slipper but was sent a size 1,450 after manufacturers failed to spot a decimal point in his order, was widely reported. I first saw it on the Telegraph site but they've done their Ministry of Truth Records Department thing and now the link leads to a story telling you about the hoax so here's a link to the same story at the Mirror: "Gigantic XXXXXXXXXXXXXXXXL slipper delivered to man who ordered a size 14.5 but got a size 1,450". The Mirror story also guesses a number of X's but I don't recall this from the original so will ignore it as the Mirror's addition. This tells us, in a 'quote' from Mr. Boddingham, that the slipper "measures 210 x 130 x 65cms".

The original story said that the factory in China thought the shoe was for a shop display, so thought nothing of the strange order. It does not explain why a shop display would order a 7ft slipper using shoe size terminology or how the extra materials or shipping costs were met.

There's a proper bit of journalism over at the Guardian, "Was the 7 foot 'monster slipper' really a PR stunt?", which covers much of what is wrong with the article. The PR company say the story was from the retailer and they assume it was true. The retailer said it's definitely true. This also has some discussion of Joseph Jennings, who apparently works for the company, and his visual similarity to Mr. Boddingham, pictured with the giant slipper article.

I feel slightly strange about the idea that missing the decimal point out of 14.5 would naturally lead to 1450. I suppose it might be that the ordering system always takes two decimal places and it was really 14.50 that was ordered. I don't know why failing to spot a decimal point has to be a "translation error" by the Chinese, and not just an overlooking. This might be reasonable as a translation error if we remember that different cultures use decimal and thousands markers differently, with some using comma for the decimal mark and dot for the thousands separator (not China, though). Even so, the dot isn't three places from the end. In China, according to Wikipedia (so it must be true) the dot is sometimes placed every four digits, but no mention of two.

Anyway, happy this is a hoax and ready to leave it I idly decided to check the numbers. According to Wikipedia, UK shoe size is based on the length of the "last", the foot-shaped template over which the shoe is manufactured, measured in barleycorn, a basic Anglo-Saxon unit used as the legal definition of the inch in many medieval laws in England and Wales. There is no precise relation between the last and the eventual shoe size (this is why two styles of shoe claiming to be the same size can be so different and why I can't tell if I'm a 14 or 15; a real pain because shops don't generally stock those sizes but I don't know which to order online) but we can safely assume the size is similar to that of the eventual shoe.

Wikipedia gives UK adult shoe size as 3 x the length of the last in inches - 25. A barleycorn is about one third of an inch, which is where the 3 comes from, and the -25 takes out the child sizes. Adult size one is then based on a last measuring 26 barleycorn or a bit under 9 inches.

Size 14.5, then, would be based on a last measuring about 13 inches:
3 x n - 25 = 14.5
39.5/3 = n = about 13

Using the same formula, size 1450 would be based on a last of 1475 barleycorn, which is about 492 inches, or 41ft:
3 x n - 25 = 1450
1475/3 = n = about 492

The article claims the giant slipper is 210cm long, which is a little under 7ft. The funny thing is that the 14.5->145 error (which seems, to me, more natural) would give a last of almost 5ft, a more reasonable size for a man-sized slipper.
3 x n - 25 = 145
170/3 = n = about 57

Of course, the reason I find this sort of thing interesting is the willingness newspapers have to report stories like this without fact-checking or, seemingly, common sense-applying. I'm also annoyed that they don't bother to check even the most checkable facts - the arithmetic. That the arithmetic doesn't add up, given all else that is wrong with the story, shouldn't really surprise me, but still I can't help feel that if you're going to write this up then two minutes with a calculator would give you a flaw, even if no other alarms were raised.