SOrry. Your "verdict" about the use of antisieze on the plugs is WRONG. The stuff should be used to keep the plugs from sticking / THAT's why it's called ANTISIEZE! If you are unable to gauge the proper torque for a sparkplug in an aluminum head, you should NOT be doing this at ALL!!!!
ADDED: the proper "feel" for the tighness of the plug is the same as about a 4mm (1/4") common bolt being tightened. A 4mm bolt will SNAP OFF pretty easy with a ham-fisted effort. So be aware. It ain't like a 10mm hardened bolt with a hardened nut, at ALL.
