As I understand, the starting point looks to be that you most often deal with single digit numbers of imperial units, but in metric it's less often the case, and that's inconvenient. While I'd generally agree that a single digit is slightly easier to deal with mentally, I'd be skeptical on whether imperials are that much better covering convenient ranges. For distances similar to inches, feet and yards you have centimeters, decimeters and meters, which are pretty close, but still with added benefit of simplicity and uniformity.
Metrics allow to look into much large range inside the same system, which allows quick mental estimations; converting parts of an inch into feet or yards are less convenient. Then we can talk about areas and volumes, where metrics multiply nicely, but with imperials there's a whole set of special units.
Metrics allow to look into much large range inside the same system, which allows quick mental estimations; converting parts of an inch into feet or yards are less convenient. Then we can talk about areas and volumes, where metrics multiply nicely, but with imperials there's a whole set of special units.