It's all about 'shear strength'. The shear strength of a modern synthetic is what allows you run such low amounts of oil and continue to provide more than adequate protection. In case there are those reading this thread that don't know what shear strength is, it is simply an oil molecules ability to resist being 'torn' by the forces within an engine.
I would lay odds that a quality oil such as Amsoil, used at 100:1 provide more protection than Yamalube @ 32:1. I've run my 500 and raced it WFO (open desert - LOTS of dust, LOTS of extreme heat ) and never had a failure @ 100:1. Hell Glamis can't even kill this thing @ 100:1. All that 32:1 , 20:1, 24:!, etc... oil ratios are from way back in the day when people ran a conventional 2 stroke oil and HAD to run those ratios to provide the necessary protection to the big end bearing. Those ratios are quite simply based on tradition, not on a hard fact that they are needed with modern synthetics.