necessitate, that is where you are wrong in my opinion. It is not necessity. I think that is part of what [MENTION=21724]cyccommute[/MENTION] is trying to add to the thread.

Even on cars, we don't match up widths to rims just because we change to wider tires. Have you looked at the oversize gumbo mudders and other wide tires that people have on the trucks and cars. They don't have the ideal rim width. If they did, then that bulging tire look they are going for would be gone.

And when I owned my own planes, we had a pretty good choice of widths I could put on the rims without having to get wider wheel or an STC from the FAA.

I guess you could say that the car/truck tires and aircraft tires are designed to work on those rims, but IMO, bike tires are designed to allow for a wide range of rims widths too.