I wonder if sealing on an outdoor frame would be a good idea? Let's use the post to sill tenon as an example, if you coated the mortice and the tenon, could the coating on the tenon act as a bucket and hold water in causing premature deterioration of the tenon? I suspect it would be much slower to dry out after a good winters soaking. I think it would be interesting to look at frames 150 years from now to see how thing went, with all the newfangled devices thrown at them, from metal connector, curved members, glues used, air tight houses and such.
