The idea behind this is to alert Earth bound observers of sunspot activity which may form on the farside during the 13 day period it is masked. Theoretically, we won't be surprised when the spots swing around to our side. This may give us time to prepare for severe solar weather.
The SOHO/MDI Stanford team have recently announced success in improving the acoustical imaging of the farside of the Sun. (Yes, in space no one can hear you
The process uses helioseismicity to determine what active spots are doing on the other side of the Sun. They even provide
to see what is going on.