If you look at the design of the TB and intake elbow you will see that they interfere much more then smooth out flow. Flow is already coming in at a straight drop at this point. the fins direct the air over the vaccuum insertion point and directly in the middle of the butterfly blade.

If this is detuning the elbow, then what would we call the Needswings intake? That seems to flow pretty well and has removed all fins and stabilizers. Is the airflow distorted in their system?