Normal paracetamol dosing is less than half the toxic dose of paracetamol, and it is an incredibly safe drug at these levels.

Yes, that is the point. It is incredibly easy to go over double the normal, if you are irritated with symptoms. I know people who take three aspirin pills at once because they really want to throw a nuke on that hangover. A typical coldrex pill is 4 pills a day. It is far too easy to not even read it (it is OTC so "safe" right???? they would make it prescription if it was dangerous right???? <- this is a common logic used) and pop a pill every hour.