Repair-man do you suggest whirlpool direct driver washers should only wash on full water setting ? Is this because people tend to overload them ?
I recommend this to avoid excess pressure on the agitator shaft and the shaft seal which is built into the spin tube. The tube is pumped full of brown grease at the factory, so any seepage thru the upper sesal will cause greasy buildup inside the tub. At the same time, water is allowed to permeate the lower brake and clutch bands, causing damage there as well.
Having a higher water level reduces the load on the agitator base, rather than lowering the water level and have the clothes pressing against the base and shaft as the agitator rotates. This also allows the clothes to circulate freely and get the full benefit of the Vari-Flex agitator. When too low a water level is used, the extra pressure created on the agitator causes the top seal to wear out prematurely.
Overloading makes it worse, but is not the primary cause of upper seal failure, only coupling, clutch and brake failure.