I’ve posted this link before, but YES, the Teflon company says that high-heat drying is beneficial to the finish.
http://www.dupont.com/teflon/fabricprotector/how/how_faq.html
A quote from the link above:
For outerwear, do you still do light ironing to activate?
A heat treatment (warm ironing or tumble-drying) will optimize the performance of Teflon®.
What is not beneficial to the blanket is having the straps get tangled in the dryer and subsequently rip right off. Which is why the blanket companies say not to tumble dry them. That instruction has nothing to do with the finish itself.
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