[quote=Holice]The specific thread to use is one of those quilting myths.
Use what works for you. There is no evidence (and this is from the thread companies) that polyester threads cut the fabric. Thread is made differently now than 30 or so years ago. /quote]
The way I heard the use cotton thread on cotton fabric idea justified was that the cottons will all wear the same, whereas polyester doesn't wear the same as cotton. So you get something made of all the same materials and it stays the same better. Which made sense to me :)