Regarding the clips or notches that are put on cone shaped baffles, why?  If you need more gas going past, why not have a bigger hole? In my mind's eye, it seems like the idea is to retain the gasses as long as possible between baffles in order to allow more cooling time and distribute the sound over a longer time frame.  How do the notches affect the gasses in a way that makes for a more quite shot?  
I appreciate your answers. I've just been puzzled by this.

https://www.ar15.com/forums/armory/Can-someone-explain-clipping-the-baffles-/55-520357/
https://www.ar15.com/forums/armory/Benefit_of_clipping_or_venting_freeze_plug_baffles_/55-459299/

Forces turbulence without adding restriction.