I've always used the light coat of oil on the gaskets as this is the way I was taught and have had no problems, so I would agree with the nothing goes on a valve plate but the gaskets, plate and bolts....but I'd have to add the oil to that list.
The torquing down should be done with a good torque wrench and done according to the book. I have to admit that I rarely bother to get out the T-Wrench for something like a K-Body's service valve bolts, but I do for the bigger stuff and always for head bolts.
I was at a Hoshizaki ice machine seminar a while back where the speaker emphasized the need for proper torque on a nut for a flaker. He asked how many guys had a torque wrench in their truck and out of over a hundred techs about three raised their hands (including me )....... and these were for the most part all refrigeration guys.
Kinda sad, isn't it?