When using a cab block it is emulating that cab and mic so I'm just curious why we would need any filtering before sending it to the sound guy? I'm not arguing I just don't understand it.
Usually it's to fix excessive highs and lows due to tweaking your preset at low volume.
If you build your preset from scratch at gig volume, it usually isn't needed as much.
Most FOH engineers would cut anyway just to fit you in the mix, that is the main reason I have cuts on my patches; to make my presets as 'mix ready' as possible as sometimes the FOH person isn't a real "engineer", so I want to control my tone as much as possible.