To the Editor: I appreciated Harris Hyman's informative article on nail power (Practical Engineering, 2/94), but I question the assumption of the superiority of joist hangers over toe-nailing. Long before joists hangers were in popular use, a carpenter (who in my 19 years of experience I still regard as the finest I ever met) taught me to toenail joists and rafters to headers and ridge beams by stitching both sides of the joist or rafter with 8d sinkers about 3/4 inch apart and staggered. We'd blunt the point before it was driven. It made for dainty work; no rigging axes or even waffle heads on John's jobs, thank you. Years later, a change order drove the lesson home. The