Just remember, on critical fasteners, i.e. main studs, rod bolts, head studs, etc., all fasteners are usually torqued once, then re-torqued in sequence, one at a time. Fasteners stretch after the initial pull and sometimes it takes 2-3 stretches to get them to settle in. It's not uncommon on rod bolts that require a stretch spec to have to seat them, unseat them, re-lube, burnish in the mating surfaces, then seat again.
When you start introducing (and relying on) torque specs for small fasteners, such as pulley fasteners, valve cover fasteners,
oil pan fasteners, etc., then you open another can of worms. To be honest, I've been in many race shops, including Valvoline engine labs dealing with Cup motors, and I've never seen anyone "torque" an
oil pan bolt/stud...
If a torque spec was required for all fasteners, then you'd hear a lot of small block guys (Ford, Chevy, etc.) whining about the same
oil pan leaks, valve cover leaks, etc. It simply doesn't happen with them on the same scale as it does with the FE. As a matter of fact, you would be torquing/retorquing for a week straight, as you go around trying to compensate for the compression of two oil pan gaskets, a windage tray, etc.
IMO, the issue here is the engine family, being compounded by aftermarket parts and a block material that shrinks/grows with heat. The equalizing bars/plates that go around the oil pan flange are a good idea, as is the use of a sealant on all surfaces. A fiber lock nut probably wouldn't hurt either...
The fact of the matter is that an FE *should* have the easiest oil pan to seal up: one piece gasket, all flat gasket surface, large number of fasteners, etc. You just have to wonder why it has more trouble sealing than the other engines...