A feeble attempt to show how I attached the shelf. The legs are tapered, but I cut the dado for the shelf before I tapered them in a V block jig on the table saw. The hole for the dowel was also drilled before tapering. As to the shelf floating in the rear legs in so far as to compromise strength, the legs are 2 1/2 in. sq. at the top with 4 1/2 in. of tenon, 1 1/2 deep. glued and doweled. I feel that should be adequately strong, I guess time will tell. I came up with the method, so I guess I can't blame anyone else if it fails. Thanks for the interest. George