T2, yes, I often add xylitol to my OPing, it's nice with coconut oil. I posted about this here some time ago. I also swish with xylitol itself for a few min. at a time.
Could you tell me what MO and HM stands for? The gist of your post as I understand it, is that swallowing the oil after OPing is probably not going to hurt us. You may be right, on the other hand there may be an important psychological element to spitting it out, getting rid of the "bad stuff."