David Mechner (6d) on Go
David Mechner's (6d) advice on how to study and improve in Go is too lengthy to reproduce here but it's worth a read. Mechner is another former insei and is apparently working on a program that plays Go.
His Go biography and his overview of the ranking system and how it differs by country were interesting to read. David studied under Oeda Yusuke (9p) who was also Michael Redmond's (9p) sensei. One of the photos linked to his bio gives you a sense of how unglamorous the life of an insei is. If you have the desire to become a pro, keep in mind that, like many competitive vocations, it's a long hard road and there isn't much room at the top.