Final answer:
Herb Clutter was known for his cleanliness and tidiness, which were pertinent to the crime because it suggested a personal connection to the perpetrator.
Step-by-step explanation:
One of the habits Herb Clutter was known for was his cleanliness and tidiness. He took great pride in keeping his home and surroundings in impeccable order.
The cleanliness and tidiness of Herb Clutter's home were pertinent to the crime because it baffled the investigators when they found no signs of disturbance or forced entry. The fact that there was no evidence of a struggle or disruption in the house led the authorities to believe that the perpetrator might have had some sort of personal connection to the victims.