Suppose the following beam situation within a mundane building (viewed from above). Assume vibration and torsion aren't issues. Suppose we have a choice to span a gap in 2 different ways:
(Grey = supporting walls, black = beam/s. Not to scale)
Clearly (B) isn't usually valid for prestressed precast lintels, unless the manufacturer advises otherwise, because of the risk of breaking over the midpoint, because the tension will be at the top, but the tensioning wires at the bottom. But if the beam is a steel profile, or perhaps timber, which handle both compression and tension fairly well, is there any common reason to prefer (A) to (B), or any matters to take into consideration before adopting (B)? Or any reason (B) would be weaker than (A) if it used the same profile beam/s?
Or is (B) always likely to be the obvious preference because it provides more continuity hence stiffness, has fewer connections hence freedoms/modes of failure, and is likely simpler and cheaper to fabricate?