As with the premise of Colemak, the idea is plausible: keep everything close to the home row and take it one step further by limiting all motions to 1 key unit at most (“1 key unit” is the space occupied by an alphanumeric key and is often expressed as “1u”). Whereas having many layers leads to other compromises with the layout of the thumb cluster, such as a key on the left hand activating layer 1 and a key on the right doing the same for layer 2. I suspect that the apparent comfort reported by many comes from a combination of factors not limited to the keyboard layout, such as being more mindful of one’s typing technique, fixing their posture, getting a split keyboard with a column stagger, finding the best key switches and the right keycap profile for them, and so on.