Thanks for taking the time to post this essay; I know they take a lot of effort. I have never wanted to be messing with a camera while I had bedding compound about.
There are lots of ways to skin a cat, and likewise there are different techniques to bed. I mask the front, sides, and bottom of the recoil lug. The clearance makes the barreled action easier to get in and out of the action, and also ensures that I am not scrapping off the edges of the mortise bedding as I take the action in and out. More a matter of personal preference than anything.
But with all due respect, I do think you are doing something significantly questionable in your bedding. I really think the back of the trigger abutment should be masked so it is not functioning as a secondary recoil lug. It is not designed for that, and can lead to splitting in the tang. (Know that crack that so many Savage 99's have? That is from the tang bearing recoil.)
When the cartridge is fired, the recoil pushes back on the recoil lug and flexes the walls of the stock around the magazine out, and the stock shortens. (That is why so many old Win70's have a split in the wood behind the magazine--from that outward flex. That is also why crossbolts help--by holding the sides in.) That means that there has got to be some "give" between the length of the action and the stock or forces are being directly applied to the stock in places you don't want. That is why the rear of the trigger abutment on a Win 70 needs to be masked so that it is not a bearing surface.
I also believe you do not want the stock bolts, the magazine, or any other surface of the action functioning as secondary recoil lugs.
