I would say that the guy quoted is covering a defect in the fuel delivery of Kawasaki engines and is incorrect about most things in that quote. Yes, ethanol added gasoline stores with more problems than a gasoline blended without but he is totally incorrect about blend rate, vapor locking, and engine build tolerances.
This topic has been covered on this Forum and other places and there is a lot of misinformation about ethanol blended gas. The only tested and confirmed engine problems in the combustion of E-10, AFAIK, is in high power outboard marine engines. Your average small horse power lawn mower engines will perform normally as long as the gas is not allowed to sit in storage for longer than a month.