If you have the budget I'd go ahead and buy 3 skeins even if the pattern only says 2. I say this because I just substituted a laceweight yarn for a pattern without a written gague and even though I bought enough yardage for the pattern, and knit on the size needle reccommended, I just realized that I don't have enough yarn to finish as I guess I'm knitting at a looser gague than the designer. Better safe than sorry and if you have an extra skien you can alwasys make something small with it.
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