My intentions were not that the size of the beam would be difficult to find but that it is a bugger to handle and in upper reaches of the frame, at that. All in all it's just me speculating. I would add to Mike's points of the king post getting in the way. When ever I construct a king post truss it is always in the way if you are using the attic space, barn, home or what ever, and any strut work makes it even more so.

Ron, I think you interpreted my words well. To clarify a bit more, most dropped ties are within a foot of the top plate, so it is still in the ball park. They had to create a joint there anyway, so to making it a through tenon with an extra peg and/or even a wedge on a half dovetail would be less work and material than the ridge and post set up. There is a lot of functioning dropped tie barns out there with common rafter, so it works.

Another approach would be the english tie but, from my perspective that does not handle thrust from common rafters well. The english tie gets your tie right where it is ideal and to top it off barks for a principal rafter and common purling roof system, changing how the roof system works in comparison to a common rafter system.

Ken, how were the rafters tied at their peaks if at all, other than the peg through the ridge? I used mortice and tenon to connect the rafter to the ridge. They were not laid on top as in the photo. I like that as an alternative, as long as I was not having to join the rafters at the peak. This example has me wondering if the cruck was to shrink than did the ridge drop too? It's like chess, 3 moves ahead and I stall out due to to many options, then you can go back over the game and follow the notations to see what happened.