About vented systems, woofer excursion rises below fb, and it should be limited to use above fl in high-output situations. Use of EQ to increase output below fl wouldn't be cool in a vented system if output was high, and really not that beneficial even at moderate outputs.

I suggested the EQ scenario for sealed systems, and my point was that if a sealed system is equalized to mimick the frequency response of a vented system, then all the other characteristics like damping and group delay will match too.