There is a guide to oils on Mark's blog. The gist is that the more saturated fat and less omega 6 the better. So peanut oil is omgwtf terrible whereas coconut oil and macadamia oil are the best. Things like ghee and beef tallow which are also low in omega 6 and high in saturated fat seem to be the best and things like olive oil and avocado oil which have moderate amounts of omega 6 seem to be good in moderation for salad dressings.
Stabbing conventional wisdom in its face.
Anyone who wants to talk nutrition should PM me!