Currently when you use the mallet on a roadblock it'll turn it into a slab but it will not update the collision box, the reason for adding the collision box is to prevent any "soul sand" issues, such as going through doorways at the end of a road, or climbing stairs / half slabs on the edge of the roads.
Currently when you use the mallet on a roadblock it'll turn it into a slab but it will not update the collision box, the reason for adding the collision box is to prevent any "soul sand" issues, such as going through doorways at the end of a road, or climbing stairs / half slabs on the edge of the roads.