Considering the UK and other countries use the DNS lookups to block access to illegal sites then you could run the risk that a innocent search term you start to type might actually send a DNS query for an illegal website.
Think typing a search for 'dog sex in a Labrador pup' would at some point send a DNS look up to your ISP for dogsex domain which could actually exist and be on the banned list
Biting the hand that feeds IT
