I think that using seamless products on your hair reduces the mechanical damage done to your hair, and since mechanical damage is one of the causes of split ends and breakage, I think that consistently using seam free products will, over time, improve the overall health of your hair. Those tiny seams on combs can act like fine razors, scraping and scratching microscopic bits of cuticle off of my hair - and since I want my hair to manage to be 11 years old and still looking good, I really can't afford any cuticle loss!
Can I say, for certain, that since I've used this stuff I'm seeing less breakage and splits? Yeah, I can, but I've also changed a lot of other stuff in the period I've been using them, so they can't get all the credit. Do I think I would be seeing more breakage/splits than I'm seeing now if I wasn't using them? Yeah, I do, which is why I shelled out the loot, but I've got no proof, ya know?