March 13, 2003
A: FROM MENTOR JOAN LUSK IN RI
I googled "denim" and found what I could have noticed by looking at my own frayed jeans: the warp and woof threads are different. Now I can't find the same sites again but here's a related one:http://www.bartleby.com/65/we/weaving.html
The white threads are stronger than the blue in denim, but the blue seem softer; the combination seems to be a compromise between strength and softness. At http://www.cow-boy.com/roundup6.htm I learned that a similar fabric made from all-colored threads was indeed less durable.

But it does seem to me that jeans wear out a lot faster now than they used to, back when the new ones were stiff as a board and the blue indigo dye ran for many washings. Now some are deliberated "aged" - acid-washed, stone-washed - and those processes would weaken the fibers.