Guys,

This approach to the spin halyard routing is not new. There were Shearwaters with spin halyards running down the forestay 20 odd years ago. The Shearwater was one of the very earliest adopters of the wing mast and some owners tried to improve the airflow by re-routing their jib and spin halyards.

There are still Shearwaters today with external spin halyards running down the mast so I guess that even after all this time the jury's still out on the benefits?

One of the best solutions I've seen is to go internal and exit at the front of the mast above the gooseneck. The halyard then drops down to a spring loaded block at the base of the mast, runs forward, round a turning block and then back to a spinlock on the beam. From there it's the usual route back to a block/ring and then forward through the chute.