According to Astobix and other popular sources:

The Krishnamurthi astrology system devised by Shri K S Krishnamurthi is a derivative from Vedic Astrology that delves into finer divisions of time attempting to predict the timing of events more accurately.

Shri Krishnamurthy used Nakshatras and divided into finer units called the Sub and the Sub-Sub.  It is believed that the position of Sub-lords and the aspects they have is used by the followers of Krishnamurthy system to make surprisingly accurate predictions about a person. KP is widely known to be a very reliable and scientific system of prediction, perhaps a near-perfect method known to the world by far.