A thought as I Hoovered
Nightjar wrote
DerbyBorn wrote
Why do we scrub the heavy thing back and forth when it has fast
revolving brushes? Surely a single slow pass is just as effective.
ISTR some research, years ago, that showed that around
seven passes were required to achieve the best cleaning.
That number must be straight from someone's
arse given the different technologys used.
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