Yes, Tom, I believe we are only talking about straight pins. I don't think you should sew over any other kind of pin, like a safety pin. However, I also am in the camp that does NOT sew over pins---I either pin them in places that won't run under the presser foot or I stop and remove them before they get to the presser foot area.
If you need lots of 'support' to keep the two layers together, consider a swipe of a glue stick in the seam allowance area.