DIY paint booth fan question

Maybe I'm crazy, but I've painted three cars in a garage "paint booth" made of blue tarps. With a good respirator, I didn't feel the need for any fan to be pumping dust through the paint area...especially a big monster like that. I kept the respirator on at all times, kept things as still as I could, waited until the coats had set, and then opened up the garage doors to air out. Your box fans and blower are enough.