Of course the anal-retentive will then question whether the 3rd person going for help solo is thus increasing the danger because they are now hiking alone..... (but I'm just pulling your chain)

I was overtaken by a somewhat unexpected Spring snowstorm when hiking alone last Spring. I had more than sufficient clothing and knowlege to cope with it but I also was acutely aware that my safety margins had just dropped dramatically. I was 1 mile short of my goal and 5 miles from the car. I immediately turned back to the car and walked very carefully all the way back mindful that getting hurt under those conditions could be fatal - even with a detailed hike plan and a specified SAR callout time given in the plan. It was still a satisfying outing :-)