Dropped the barrel off at the gunsmith today to add the mid bead. It is actually solving another problem for me ... referenced in my post about the recoil pad. I was having a problem with the heel being over my shoulder blade when I mounted the gun and I intended to resolve the issue with an adjustable recoil pad.
After watching many youtube videos about mounting and gun fit, I stumbled across one that suggested taping a drinking straw to the vent rib to check for the correct sight picture. When I did this, using the straw as a peep sight, the heel mounted correctly to my shoulder. I had been using the wrong sight picture when mounting. In my attempt to not see too much of the rib, it appears that I wasn't seeing enough.
To me, the easy correction for this is to simply add the mid bead ... seems to take care of the uncertainty about how much rib is too much or too little