Unlike McCarthy’s book "The Road", which is dominated by sparse sentences, McCarthy includes some pretty long but intact sentences. I really love McCarthy's writing so I'm not going to second guess his motivations. I think that the beauty of this particular book lies in his depth of prose. Long or run-on sentences, when written by unskilled hands, draw attention to the sentence itself. McCarthy, however, paces his sentences so they melt into the texture of the narrative. Instead of sounding obtuse or overtly cluttered, his long prose is beautiful and layered. Check this sentence from the book out:
"That night he dreamt of horses in a field on a high plain where the spring rains had brought up the grass and the wildflowers our of the ground and the flowers ran all blue and yellow far as the eye could see and in the dream he was among the horses running and in the dream he himself could run with the horses and they coursed the young mares and fillies over the plain where their rich bay and their rich chestnut colors shone in the sun and the young colts ran with their dams and trampled down the flowers in a haze of pollen that hung in the sun like powdered gold and they ran he and the horses out along the high mesas where the ground resounded under their running hooves and they flowed and changed and ran and their mains and tails blew off of them like spume and there was nothing else at all in that high world and they moved all of them in a resonance that was like a music among them and they were none of them afraid horse nor colt nor mare and they ran in that resonance which is the world itself and which cannot be spoken but only praised." All the Pretty Horses
I wish I could write like that!