It's mostly the way the white seems to want to travel across his barrel rather than to his legs.
Ignore tovero. It's a word that should never be used. The four white patterns are tobiano, splash, frame and sabino. Each has different characteristics to the way they display and interact.
Frame tends to make top-heavy facial markings. It wants to spread out and make a bald face, much like it is on this horse. It will avoid the ears if possible though. Again, this is just demonstrating the whole 'frame' nature that it was named after - it wants to leave white on the nose and the ears, thus making the face white framed with colour.
Splash tends to be bottom heavy. It often gives blazes an 'apron' appearance, where they noticeably flare toward the nose. Splash also tends to 'slip' and make face white uneven on the face - more to the left or right, not centered. Again, splash will try to avoid the ears, but will try to cover the eyes if it can.
Sabino tends to be the 'messy' white. It likes to give the horse a chin or lower lip spot at least. Its edges tend to be less neatly defined, and often seem to roan or bleed out to the colour parts. Sabino seems to also like to keep white off the eyes, and like the other two, will also try to avoid the ears.
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I would also add that tobiano leaves the face alone, and likes to run vertical. It likes high white on the legs, and often higher in the back than the front. It tends to cross the back at hips and withers first, then the rest of the back if it's extensive.
Frame likes to move horizontally along the horse. It leaves a 'frame' of colour around the back and the belly to a certain extent. It tries to minimise leg white - without another pattern, one would expect no leg white with a frame horse.
Splash tends to be bottom heavy on the rest of the horse, not just the face. It often gives high whites on the front legs before the back legs. The edges of white with splash tend to be fairly neat.
Sabino is the catch-all for the rest of the white that occurs. It tends to be messy, and have roaned edges. It likes leg white, and belly white.