I'm looking to understand the full relationship between timing/power/kr/mods. Please, everyone add what they can to the topic to provide as complete and detailed information as possible. I am not an experienced mechanic, but am willing to educate myself given the information.
This is what I've gathered, please correct as needed...

The PCM is programmed to retard timing in the event of "knock" - or pre-ignition in the cylinders. Thus, the term "knock retard".
Pulling the timing results in loss of power - the more degrees of timing retarded the greater the loss of power. If the PCM didn't retard the knocking it would result in damage to the engine.
What are specific causes of "knock"? I don't mean " (blank) mod causes it" I mean mechanically what does that mod do that causes knock?
Certain modifications increase the risk of "knock" - the most commonly referred to KR-creater seems to be a smaller SC pulley.
"Colder" range spark plugs and intercoolers seem to be the most effective KR prevantives to a modified engine, why is this?
Not all engines are created equal, some are "KR monsters" and others seem to run the same mods without KR issues, why?
It seems that KR has got to be one of the top "power-killers" and yet so many people don't understand this issue, myself included. I think this info would be a great thing for Herc to have on his site.

Well since you asked I'll try to explain,KR is the responce from the pcm to cyl. detonation,kr is the measure of the # of degrees of overall ign. advance that must be removed to prevent det. from continueing.Detonation is the uncontrolled combustion of the intake charge,uncontrolled means the mixture ignites via a means other than spark,the uncontrolled ign.is due to hot spots in the cyl.,hot spots can be caused by uneven combustion,spark plugs that are rated to hot,lean fuel condition,breathing or exhaust restrictions,that is why an aftermarket PCM is a must for performance they fight KR with fuel enrichment,recover rate,and power enrichment.I hope this helps you understand KR a little more ,Chico.

The reason some engines are KR monsters is the slight variations in assembly. If the head gasket is sticking out just a tad in the cylinder that can create hot spots. Burrs in the combustion chamber can create hotspots. Carbon build up can increase the compression ratio which will cause more heat to build. A weak cooling system can cause the heads to run a bit warmer.

Spark plug heat ranges are based on the plugs ability to dissipate heat. Colder plugs cool off faster eliminating hot spots. Platinum tipped plugs are bad for KR since the platinum dissipates heat at a slower rate since there is very little surface contact with the rest of the plug so the tipps create hot spots.

An intercooler reduces the temprature of the air that enters the cylinder dramatically eliminating 99% the cause of pre ignition. Provided the rest of the engine is properly tuned.

Bottom line,
pour in some Motor Up and it will remove KR.

Geez that a lot of lingo...

check out zzperformance.com for a thorough explanation.