Isn’t cfm that is lost in the hose? Not so much water lift.It is good reading!
Back in them days, it was more info them most anyone eles talked about...
Most 2" hose will handle 300 cfm of airflow well at 12HG (164" WL) before these losses get too great.
But since vacuum hose losses about 25" WL/100 ft; it is wise to limit the length that you use.
Since in residential cleaning only 100 ft or so is needed, this is not a problem.
The 10' whip hose that is often used with the 2" hose to fit on to the 1.5" tubed wand is likewise not too restrictive as it will allow up to 250 cfm of air flow thru when used at this length.