The problem is lack of good evidence for laundry hygiene recommendations.
The laundry hygiene section in Wikipedia is quite good
http://en.wikipedia.org/wiki/Hygiene#Laundry_hygiene
"Of concern is recent data suggesting that, in reality, modern domestic washing machines do not reach the temperature specified on the machine controls."
At least one UK expert suggests washing some items such as towels and bedding at 60..
http://www.thehygienedoctor.co.uk/dont-get-your-knickers-in-a-twist/
And from the Hygiene Council 2008..
"Launder clothes, linen, towels, and other fabrics at a high temperature (above 60°C)
If a lower temperature is recommended or you prefer to wash at a lower temperature then a laundry disinfectant should be added particularly for the laundry of small children or other contaminated items
Launder heavily soiled items separately
Dry clothes immediately after washing to prevent build up of germs
on damp items
Run washing machine empty at a high-temperature occasionally
to prevent it becoming a reservoir for germs"
I still prefer to wash dishcloths, towels and bedding at the higher temperatures.