Myths

A heat shield made out of aluminum is nothing more than a heat sink. The heat from the heads going to the manifold, with the throttle body attached to it will be a far greater source of heat compared to the exhaust manifold that is not attached to the ...

This isn't so much a myth, as it is exaggerated. The lines were put in by GM for cold climate conditions, which is said to cause ice to form on TB, which could cause a lot of problems, like a stuck open condition that can cause an accident. There have been no known reports of this happening, but there hasn't been any research either.
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There are several different versions of this myth floating around.

Here is one view on why electricity and boost don't mix: Click Here!
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I'm going to keep this short, because its a simple concept. For years people have been spreading the word that a 160 stat will cause problems. This is true, as it hurts gas milage and MAY cause the cylinder walls to wear faster due to less expansion. If your fan turn on times aren't matched, it can allow a cycle of 160 to 220 degrees back and forth, which will contract and expand the cylinders.
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IAT stands for Intake Air Temperature. It is a simple thermistor that changes its resistance according to the temperature it is at. The idea beind this modification, is that by changing the resistance to that of a cooler interpreted reading, you will get more fuel. While it is true that you will dump more fuel...its false that this is a good idea. Running rich is bad for performance, so you are just wasting your time with adding more fuel in this fashion.
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"The MAF sensor will compensate for your mods".

No, it wont. It will accept mods, including boost a lot easier than a MAP sensor setup did, because the computers are programmed with the ability to read boost values and higher airflow through the MAF sensor. However, the computer is programmed with hard set tables for the MAF sensor inputs to be converted to g/sec of air. The problem with thinking that the computer will tune itself is that it really doesn't tune. It just adjusts to keep the engine running.
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