Just for reference, a washtub - with or without boards - has exactly one use: they are fireproof, and therefore can safely be used to block traps like the one in the Boar's Head Inn basement (one trap is a poison gas vent; a second trap shoots a fireball at the poison gas vent), or in the Black Cove.
This is the reason why you don't see barrel lids anymore. The downside to carrying around washtubs for this purpose is, they weigh 10 pounds each. Barrel lids weighed about a pound, if I remember correctly.
This has nothing to do with crafting, but you called the washtubs "Completely Useless", and the ones with a board are just as useful here as the ones without. "No Effect" would be more accurate.