Actually, forgewoods were not hardwoods, they were Port Orford Cedar. They were made by cutting wood blanks 1 1/4 inch on one end and tapered down to 5/8 inch on one other end. Then these blanks/boards were compressed to 3/8 inches from end to end and cut to 3/8 inch square stock. These, in turn were doweled to 11/32, 5/16 and smaller diameters. Not only did the original forgewood process yield a denser, stronger and heavier arrow for the diameter and spine than uncompressed cedars, the process also yielded a very weight forward shaft. I still have a couple dozen. Nothing shoots better. And no, they're not for sale.
The Alaska folks were using the same process with Bob Sweetland's original equipment, but they are no longer producing shafts.
Most compressed shafts nowadays are just run through dies, which compresses the outside fibers of the shaft, but not the entire shaft. Still yields a heavier and slightly more durable shaft at a given spine than uncompressed cedars.