This is just good old fashioned snake oil.
Modern powders are progressive burinig powders and the wad type, wad pressure , crimp depth and forcing cones all play a part in developing the fire in a very progressive way.
Lengthen your forcing cones and the first thing you will notice is much dirtier barrells as you are now not getting a full burn and if you put your favourite rounds over the Chrony you will find that they are not going as fast. Recoil is generally reduced by the drop in velocity
Next thing you do is get a faster burning powder and guess what your speed is back up but so is recoil.
If pattern quality is a problem buy better shells or shoot lower velocity shells, if recoil is a problem shoot better quality low velocity shells.
There is nothing really new in shotgunning, it was all sorted out in the 1800's and that remains true to today, but there are plenty of snake oil salesmen out there who will tell you different in an effort to part you and your money.
Hotrack
