FACT: in the days of VAR and ADFs, two aircraft flying on reciprocal tracks at the same level on the same airway had a better chance of BOTH being struck by lightning at the same instant in time than of hitting (or even seeing!) each other.
FACT: If you buy a lotto ticket on Wed for the Sat draw, you have a better chance of accidental death before the draw than winning it - so what?
Airservices Australia General Manager ATC announced a national route restructure based upon enroute nav RNP1 or RNP2 for completion by 2010 early this month. Offsets in enroute phase, if you're talking 100m, are to all intents and purposes invisible to us. If you're ADS-C we might know about it by alerts (dependent upon parameters in our system) because your intent group doesn't match your flight plan that you submitted. Route structure really determines if offset is going to help.
The only real fact that matters is if you're planning to be at the same point, at the same time, at the same level as another aircraft, these days "big sky" theory ain't gunna help.