MatchCrv on a surface

I have two tangent surfaces (split by the diagonal line top left to lower right).
I have a curve that I have pulled to both sections (yellow to the left and black to the right).
The Pull has made the segments G0. Is there any way to make them G1 and on the surfaces?

I was taught that whenever you cross two surfaces like this you will lose a G. So here you’ll have to increase the surface matching to G2 in order to have G1 curves.

I never understood why that is, because intuition would tell me that curves on surfaces should have the same continuity as the surfaces.
But from experience I can confirmthat indeed you go down one g-level.

Something in the maths I guess. Maths isn’t my strong point…