So according to the above info, detonation most likely occurs in places other than the dead center of the chamber, thus running colder plugs doesn't help that much for true detonation and definitely doesn't draw or pull away heat from the chamber or anything
silly like that. Colder plugs prevent pre-ignition which occurs 160 - 180 BTDC and possibly detonation induced pre-ignition because it minimizes the plug from becoming a heat spot. This is apparent from
this thread showing detonation occurring away from the center.
Detonation always occurs
after the initial spark when the remaining gases have circulated inside the chamber, usually away from the spark plug.
Time spent inside the chamber allows for the compressed gasses to mingle with the heat remaining on the piston or wall to reignite the gases. That's why when you advance the timing, you allow more time for the gases to remain in the hot chamber, allowing an opportunity for the gases to ignite. When you retard timing, you get the gases out of the chamber quicker and reduce the chance of detonation.
Pre-ignition will
not be indicated by a knock sensor and is almost impossible to tell it's happening before it's too late.
In his article, the writer seems more concerned over pre-ignition damage because he deals mostly with 1hp/1cu. in. engines which can tolerate a little detonation. We have to worry more about detonation because we deal with 2.5hp/cu. in. or more with turbo upgrades.