nice!

similarly,

    var oldPlaceObject = map.placeObject;
    var newPlaceObject = function(x, y, type) {
    	if (type !== 'block') {
        	map.placeObject = oldPlaceObject;
        	map.placeObject(x, y, type);
            map.placeObject = newPlaceObject;
        }
    };
    map.placeObject = newPlaceObject;

was my solution to multiple levels ;).