Considering the pressures and turbulence which will be present in the cases, its unlikely gravity has any effect at all I would think.

Imagine the certifugal (centripetal if you prefer) forces when the bearings are spinning at 12,000 rpm. Is it likely that any oil dripped 'onto' the bearing will do anything but be flung straight off? Much like a drive chain and sproket...

One can only assume Honda knew what they were doing, but it is interesting to work out what that was!

Again, thinking in straight lines and 90 degree bends etc is probably pointless once the engine is spinning, as all those nice easy paths will be meaningless.

I'm not a fluid dynamics expert, but I do know enough about aerodynamics and jet engines to know it isn't as simple as it looks!
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