From what I have see rafter pairs are always aligned to meet at the peak of the roof. This obviously is required for rafters that join to one another. But what about when a plate or ridge beam is used, is there any reason that the opposing rafters cannot be offset or alternate?

The same thing goes for floor joists that connect to a horizontal beam, must the joists on one side of the beam align exactly with the joists on the other side? If these could alternate then one could use a through soffit tenon secured by wedges on the other side.

Any info or comments appreciated, thanks.
Chip