reinforce the heel?

My socks just don't seem to last long (which is why I knit so many) but I want them to last longer. I usually use 100% wool, sometimes worsted wieght and I wear them just in the house as lounging around socks, not in shoes. It happens with 100% wool sock yarns too. I've heard some people say stranding a piece of nylon in when you do the socks but that sounds uncomfrotable.
So lets hear your ideas sock knitters!
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War doesn't determine who is right: It determines who is left
-That's OK, I wasn't using my civil liberties anyway....
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Reading: Barbara Kingsolver
Knitting: socks
I'm Femmy on Ravelry