Shouldered Mortise & Tenon

A. Beveled: We use this attractive and efficient joint on all of our main posts, and elsewhere throughout the frame.
B. Square: This joint is slightly stronger in that it can resist upwards cantilever type thrust sometimes created by a knee brace between the joint and a strong downwards force.

In both versions of this joint, the shoulder takes the lion's share of the weight, and the pegged tenon's main job is to hold the girt in place.