This is true for a threaded connection that is carrying a load. In the case of a spark plug, the only reason to apply a torque is to crush the gasket or seat the seat. Only a very small amount of preload is necessary to prevent the plug from vibrating loose, compared to say a wheel stud, or head stud, that is carrying a lot of load with a high preload value. For spark plugs, you should still follow the instructions on the box, in order to achieve a proper seal. The seal is a function of the seating depth, not a torque value.
Your statement about cooking off, is completely inaccurate. And is exactly the opposite of what anti seize does on a spark plug.
Perhaps I wasn't clear or you misunderstood.
Here is a very simple test for you. Add anti-seize to a new set of spark plugs on one banks plugs, and none on other. To speed up the processes, only hand tighten plugs (sung). Drive normal. But also bring your engine to operating temp and let cool down 8 hours as often as possible (3 time every 24 hours), again this is to speed up the process. Soon you'll hear a cold start-up tick/pop, which is hot gasses passing the spark plug(s) threads. In time, tick/pop will be present even after warm-up (danger sign). Continue driving with more, heating & cooling cycles. After a good amount of run time and heating and cooling cycles. My bet: Side without anti-seize will have more loose spark plug and easy to remove. Side with anti-seize, spark plugs will be hard to remove, feeling like cross-thread in.
BTW:
I did not say "cooking OFF" as you stated!
I said: If threads then get hot gasses blow-by. The anti-seize will cook into threads, making removing plugs very difficult. Meaning if spark plugs begins to "walk out" then hot gases will pass threads, mixing with anti-seize. The combination, results spark plugs very hard to remove. Which is the opposite effect one is looking for when using anti-seize. The good part is, as the mix cooks. It also halts the waking-out. But I've had to use extreme measure to remove these anti-seized plugs. Even to the point of using penetrating oil in tube repeated run engine and cooling, 3 full tanks of gas with 44k. Where even after all that, I had to use a 3/4" breaker bar to get a plug out. I was shocked and relieved. I didn't bust the plug in the head or damage threads. Not something I want to do again.
Additionally you say "only a small amount of pre-load, is necessary to prevent the plug from
vibrating loose! "Vibration" is not so much the issue we need be concerned with, in properly installed plugs. It's how many "Heating and Cool cycle" (expansion & contraction) that is of the most concern, IMHO. This why mileage is a poor indicator of spark plugs walking-out. If one drove 365 miles until shutting down engine to cool, and did so once a month for 10 years. Which would be 120 heating & cooling cycle within 36,500 miles on engine. Spark plugs would be near the same torque. But another may drive let say; 1 mile and stop, every 8 hours, 7 days a week for 10 years. This also would be 36,500 miles. But would be 10,950 heating & cooling cycles. These Denso spark plugs in a 4.7L, would be loose.
Torque is used to insure crush washer is seated properly. This is what is used by those that have a torque wrench and aren't to lazy to use it. Which insure seating properly and evenly. The "box" instruction are general for any vehicle, without use of addition special tool (torque wrench), other than spark plug wrench. Which shows 1/4 to 1/2 turn after hand sung. Not as accurate at seating with a torque wrench.
Dig into Toyota FSM or Denso web page. You'll find torque specs also. Additional Toyota School and Denso web page. Has indications and notes, about reducing torque when threads lubed. Which I've posted in this thread.
