That's a funny and incorrect explanation for two reasons:
1 - crochet and hooked bead are the same thing, just depends on whether your talking French or English.
That quote comes from the Wikipedia article about the ISO standard and lacks sourcing. The actual standard is behind a pay wall, so I can't confirm whether ISO actually has differentiated between Crochet and Hooked Bead, which would be very strange.
http://www.sheldonbrown.com/gloss_cn-z.html#crochet

2 - 700C is a french size. The ISO match is "622." Explaining the C by referencing ISO makes no sense. (The French system defined the outside tire diameter. 700a was a larger rim intended to fit a narrower tire, resulting in a 700mm outside diameter, while 700c was intended for wider tires, still resulting in the same outside diameter)
http://www.sheldonbrown.com/tire-sizing.html

here's wikis take on it

http://en.wikipedia.org/wiki/ISO_5775


and:

For wired-edge tires the ISO designation lists the width of the inflated tire and the diameter with which the tire sits on the rim, both in millimeters and separated by a hyphen: 37-622

For beaded-edge tires the ISO designation lists an overall diameter code (16, 18, 20, 22, 24, or 26) and a width code (1.25, 1.375, 1.75, or 2.125), defined by measurement tables given in the standard, separated by a cross: 20×1.375

For rims the ISO designation lists the rim diameter (where the tire sits) and the rim's inner width, both in millimeters and separated by a cross, along with a letter code for the rim type (e.g., "C" = Crotchet-type): 622x19C

source: http://en.wikipedia.org/wiki/Bicycle_wheel

None yet.

Interesting, but it doesn't explain the usage where the 'c' is appended to designations for the tire size rather than rim size. And most clincher rims these days are designated as hooked-bead type rather than crochet-type (Sheldon was of the opinion that reference to 'crochet-type' was because that was the French term for hooked rather than any different rim design).

Still seems to me that the 'c' appended to bicycle tire widths is simply an error in notation.

This ^^

I started with 32s on my Aurora, switched to 28s and loved the difference in the amount of effort that it took to pedal. I didn't really notice much at first until I had a problem with a 28 and put one of the 32s on and it felt like I was struggling to pedal. I got a fixed gear bike with 25s on it. It felt even better. Then got my roadie bike with 23s... Now I hate fat tires. Unless it's the beer..

Most people don't have to deal with the wide range in tyre sizes we do at our co-op as we see everything from the common to the obscure and try to hold on to those rare / obsolete rims / tyres in the event someone might just need them and stock a pretty wide range of tyres... or will order them in for people as many obsolete tyre sizes are still in production but rarely stocked by mainstream shops.

Confusion abounds and the best way is to use the xx - xxx system as then you have a high probability of matching tyres and rims.

With fractional wheels and tyres still in wide useage this adds a little more confusion to the mix as there are so many 26 inch sizes out there it can be easy to make errors.

I use three different 26 inch sizes on my bikes and none are interchangeable as they are 559, 590, and 597 but all say 26 by x where several are fractional and the rest are the more common mtb standard of xx-559.

I now run 7 different rim sizes and used to run an 8th when I had a British roadster with 28 by 1 1/2 tyres (635mm)... Canadian roadsters also ride on a 28 by 1 5/8 by 1 3/8 which is really an xx-622.

Anyways... everyone seems to have a happy place when it comes to tyres and your size, riding style, and what you carry will also have an effect on what tyres work best.

When I mountain biked a lot I always ran a narrower than usual as at my weight the 2.3's that people were running just resulted in too much float and drifting whereas a narrower tire gave better contact pressure and traction.

sorry for late reply...I'm not gonna say your math is wonky, because I'm not confident that mine isn't, but I came up with a different discrepancy- about 1.2 miles on a 45 mile ride*. This was after a series of calculations that basically confused the crap out me- figuring out how many revolutions a wheel of circumference 'x' would have to make to roll 45 miles, then multiplying that by circumference 'y' to see the difference...along with the conversions between metric and English units, I could have very well screwed up.

I should have "shown my work" so I could go back and verify my results


* I shouldn't be so quick to discredit myself, but looking at this now, it seems highly improbable. Perhaps I used centimeters in one breath and millimeters in the next or something like that