yeah, one thing to add to all of this is would be that the actual bags/boards one puts their books in is about a tenth as important - if not less - than the actual environment the books are in.
i mean, Curator books were stuffed what, 10-12 to a magazine bag and stacked in bricks inside a museum vault? Church's books sat unbagged/boarded in piles in his basement for 30 years... Larson books were what, in a closet somewhere?
if you maintain conditions in which there is low temp and low humidity, as long as you're not handling them often, i'd be shocked if you even NEED bags and boards. all the other stuff is just overkill if you can afford to maintain the right temp/humidity conditions