Attilio Anthony John Wagstaffe
Going along the lines that Japanese culture has a farming tradition that goes way back when, would suggest that making a furrow in land, much the same way as ploughing, would need tools that chop into the earth.
So moving forward foot by foot would seem to me a reason to how the sword and all other implements of farming and weaponry would have it's basic movement in tsugi ashi....
Just a thought, but I may be wrong.....
Did you mean to say that the sword is a farm implement? Because it isn't. As far as the sword goes, the extent to which life in the fields informs its basic movements is probably rather minor.