Reading the comments on drywall in the July issue. I guess some history is in order. 100 years ago homes were built with lumber that was not consistent width.
to make sheathing simple the studs were flush on the outside and plaster and wood lath evened out the inside. Consistent stud widths and rising costs meant something else was needed for low cost housing. When drywall came out It was designed to be in two layers, this gave a thick wall like plaster. But the real reason was to speed install. The first layer went up and down and was to be nailed but not taped. the top layer went left to right and was nailed only under the joints, adhesive eliminated the nails in the field. The result was a wall that thumped like plaster,but it still dimpled when hit.
hoot