hopefully this weekend... gotta take pictures first. I did some measurements last night (and again just now)... the gesshin hide is very very similar to in geometry to the gesshin heiji (though they dont look similar with regard to that). THe Gesshin Hide is about the same thickness (of the spine) at the handle, but doesnt taper as quickly in the middle, so its a bit thicker at the spine there. However, the last 1/3rd of the blades are about identical in spine thickness. What is really interesting is that when i measure thickness behind the edge, they are literally nearly identical. They are both 1mm thick about 1cm from the edge all the way from heel to tip and about .5mm thick about 5mm from the edge. Again, not having used one yet, i cant say definitively, but i expect performance based on geometry to be similar to that of the Gesshin Heiji.
Oh... and bad news for the leftys (sorry K-Fed)... the blade is 50/50 ground, but the choil/machi area is ground like a right handed yanagiba. Doesnt mean a lefty cant use it, but it was clearly made with right handed person in mind.