Polygon clamping goes very wrong

Hi everyone, i experience some strange problem with a set of polygon, they are not campled as they should be, some of them are hidden and the others create a strange bug where (i guess?) we see a transparent (elevated) copy of the polygon hiding some others, try to move the camera while looking at the polygon to experience it

My geojson seems to be valide ( i have tested it with geojsonlint )

Can anyone tell me what is it going on ?

Sandcastle