It sounds to me like Paul is interested in furthering the genetics of hickory, a worthwhile project! Grafted clones are just going to keep things where they have already been, seed would further things along. I believe the U. of Nebraska distributes seed from improved varieties.
I also sell seed through my
website from a tree that makes nice shaped nuts that are easy to crack into halves. The nuts aren't very big, but they have that nice oval shape. Also, if you use hickory nuts for different purposes other than just shelling out nut meat, it doesn't matter how big the nuts are or how easily they crack out. I smash and boil them, the nut meat floats to the surface after a little while and I drink the broth. I write about it in an article on my site. I think hickory trees are amazing beings and its good to hear of other people interested in working with them.