Safety Tether

[afw]

The commercial safety tethers seem always to be made of webbing, with
about 6000 lb. breaking strength. I am thinking of making some tethers out
of 1/2-inch three-strand nylon, which has about the same breaking strength.
The reason that I am planning to use rope rather than webbing is that I trust
my splicing ability more than my sewing ability.

I will use a snap shackle at the harness end, just as do the high-end
commercial tethers. The tethers will be double legged, with one leg
being 3 feet long and the other six. At the end of each leg, I will use
an eye-splice to attach a locking safety hook.

The rope will pass through the attachment eye on the snap shackle.
Instead of using a splice, I am thinking of seizing the bight of rope together
at the shackle.

How does the strength of such a seizing compare with that on an eye splice?