multiple strings ws2812 chip led
Yes, it should not be a problem with a fanout of 8. There are no pullup or pulldown resistors inherent in the WS2811 chips (+/-1uA input current), so we need only be concerned with the load capacitance of 15pF x 8 = 120pF maximum, so a 10mA drive will add less than 50ns (10% of the shortest time in the protocol). Something like an Arduino will have more drive current available than that. 

Of course you can just send repeated data to a single string rather than fanning out from the center of a star.