Erik, I believe what he is referring to is either setting a stain using heat or bleaching the carpet using heat for too long. I recommend pulling 2 fibers that are stained with red, treat one with an oxidizer like stain magic, stain zone or peroxide/ammonia mix. The other fiber, treat with a reducer like Red 1, Red Relief or Red Vanish. Use a wall paper steamer to speed up the process and see which product removes the red. Then proceed with the rest of the stain. Especially on stain magic, get spot as dry as possible before treatment. The caution is in the heat, use the steamer and check the spot every 30 seconds to see if it is responding. Do not use heat with the oxidizers as it can cause bleaching if you are not careful. If the reducing agent works the spot will often turn yellow. clean and rinse the spot, dry and if the yellow remains, treat with the oxidizer and cover with plastic wrap. These products and methods will work 90 percent of the time.