I'm old and weak, so for shooting groups I use a bipod with a hard hold on the shoulder. This is my heavy barrelled Savage 12FV, 5 shots at 100 with handloads. I also shoot a heavy barrelled AR15 the same way, this simulates the way we varmint hunt. Always room for a bipod, but can't always have two rests.
Now the guys that shoot the really small groups, .1' and .2's, use a front and rear rest all the time, with triggers measuring in the ounces, from very heavy rifles. I shoot next to a couple of "F" class guys occassionally and if they shot a group as big as mine the rifle would be going off the the gunsmith to fix whatever was broke.
For sighting in my regular hunting rifles or load development I use a front sandbag as a minimum and front and rear preferred. The goal is to take as much of the human element out to see what the gun and ammo will do.
To be honest shooting 1 moa groups isn't hard, with a rifle that fits and is capable, most can learn to do that from a sling, seated or prone. Sure it takes practice and you probably won't do that the first couple of times but many people could.