I think the problem lies here: The Circle of Confusion assumed by most DOF calculators match the lens manufacturers; and the CoC used by them is actually based upon human visual acuity levels which are LESS THAN the 20/20 vision standard!
In the DOF scales on fixed FL lenses, many of us knew to use the DOF lines for f/8 even though we were shooting at f/11, to compensate for the poor human vision limits assumed by lens manufacturers!
So, as a result, when you put focus at Infinity, you get sharp detail. But when you use DOF scales to focus upon the Hyperfocal distance, your eye is able to perceive BLURRED infinity detail! My suggestion is to try using DOF calculators assuming a 1EV larger aperture than you are shooting at, to find Hyperfocal distance!!!