We probably need to add some more info to that Techinfo article, but here it is in a nutshell:
Non-Supercharged: Very critical to get any turbulence out of the intake. Turbulence restricts airflow. This is why the Series 2 guys gut their airboxes as a first mod. You can actually get more airflow out of a smaller diameter if it'* smooth, than you can out of the larger accordian intake boot. Getting the airflow laminar not only increases the actual volume and velocity, but it also gives more accurate MAF readings.
Supercharged: You'd think since the SC makes a 'mess' of the air as it compresses it, that this wouldn't be as critical as NA, but it is. Because of the SC'* thirst for volume, you need the same setup. You need gobs of air in available, and the best way to increase the volume is with a restriction-free, non-turbulent intake.