So a similar rule to Negative Comparatives in that it opens the door to multiple possibilities as opposed to one clear answer?

The plans for a building cannot be "true" or "untrue." They can, however, be structurally sound (valid) or structurally unsound (invalid).

Now, I tell you I'm going to build a house in Wonderland. I show you the blueprint. It is mathematically and structurally perfect—i.e., valid. If Wonderland were real, it would work flawlessly. And that validity is totally irrelevant to the "truth" of my premises, being that Wonderland is a real place I can build a house in.