(If the question is not 'woodworky' enough, apologies.)
We have an old couch. Springs are supported on webbing. I've re-webbed a couple of times over the years (as best I could). Now, it needs it again.
My question is, why webbing? ISTM, I could just as well screw plywood under there, and save a lot of work. The plywood would go under the old webbing, so the springs would remain tied in.
(Just to clarify the vocabulary, here it is after re-webbing: )