There absolutely is room for individual judgement wrt the rules of the road, and it is likely that many lives have been saved when drivers took the law into their own hands.
DS crossed about five lanes from fastest to slowest in order to pull over after suffering a blowout. In heavy traffic he put on his hazards and made his way across as quickly as he could while still in control of the car. Doing this just in order not to miss an exit or just in order to drive recklessly would have been unjustifiable. Doing what he did meant that the emergency services could get to him on the shoulder and help with changing the tyre (and yes he and his passengers left the car and phoned from the grass away from the highway).
I have swerved onto the shoulder either fully or partially many times to avoid large masses of debris in my lane. I used the shoulder in preference to the adjacent lane because there was never any vehicle in it.
You sometimes encounter blown out tyres or pieces of freight or large unidentified and potentially metal objects while driving, both in Ireland and the US.
Ditto deer and other large roadkill, and the same goes for deer who were 100% alive clattering across the road. I have experienced this only in the US.
I also swerved onto the hard shoulder to avoid a flying, flapping mattress heading south on the M6 just before it curves around Stafford.
If there was no room for individual judgement, you would be faced with a situation where you would drive straight through a pothole of unknown depth or over something in the road just to be able to abide by the rule about driving on the shoulder or not making lane changes without indicating. You would risk a blowout or some other problem that might adversely affect other users of the road.
I've been driving since the mid 80s in all conditions from blizzard to perfectly clear, and in several different countries. No matter where you drive, common sense comes into play, and common sense and the rules of the road sometimes don't coincide.