Offsetting-Cheap Risk Management
Offsetting is particularly advantageous on two way routes as it ensures that aircraft passing head on are at least 1 NM laterally separated.
On NAT tracks it can minimize wake turbulence from overtaking aircraft.
Random tracks across the North Atlantic are similar to two way routes as the same route can be planned for an east or west bound flight and when offsetting is utilized protection as previously mentioned is provided.
There is a safety case to be made that anything a pilot can do to strengthen defenses in the ATC system the less likelihood of lapses and omissions resulting in an incident or accident. Offsetting strengthens the ATC defense system. Operational crews are the direct beneficiaries.
Consider deciding prior to take off that offsetting will be utilized and whether it will be 1 nm or 2.