I'm not quite convinced polishing a Chrome bore has a advantage - I would like to see a before and after comparison before I give it a try
Ports .....pick up a all ready shot , shotgun wad/cup and you will notice some score marks from some makes of ported choke tubes its from the ports
Kicks , Rhino , Puregold and many more use ports in varying angles to catch the wad , different chokes have varying effects on a wad as it passes - some have ports at oncoming 90 deg others have i t in the parallel section ,other forcing cone area
some use wad catchers like Indian Creek , wad catchers are rings in the forcing cone they catch the wad for a fraction of a second
some use straight rifling like william {sumtoy } Indian Creek , M.A.D and Primos/Jelly Head have diagonal porting that has a straight rifling effect