yar i wondered this kinda thing.
with lace ups you can kinda tighten them until your fingers go blue
with boa you can tighten them until your feet go numb and then just keep on tightening them!
for consistent fit time and time again, i have tried to count the knob turns, but it never works out.
in the end i found it is best simply not to worry about it. Boa are so easy to loosen or tighten, just do so when necessary. it is supposed to be that easy and so just revel in the luxury of it all! it might take a bit of getting used to, but there it is. IMO
Just coz you don't understand it
Doesn't mean it makes no sense!