does the fully-framed chassis get a bad rap?

[jaybee]

So, picking up on some recent points from this thread, one of the limitations of the body on frame is the inability to turn a flat structure into a three dimensional structure, and solid body mounts can help in that regard. What if you built a structure into the floor in the same way that subframe connectors are often cut through the floor of a unibody? It could incorporate a heavy tunnel as Paul_J mentioned, perhaps with more structure to close the bottom of the tunnel, turning it effectively into a backbone. The various places where the structure bolts together could be shimmed and cross bolted to limit movement at those points.

Yeah, it doesn't use material as efficiently as a unibody, but that isn't what we're debating here, is it?