More Of Everything?

Continuing a thought from the previous post, imagine a Technic History containing as many volumes about the Long Night, the Allied Planets, the Commonalty and subsequent periods as we already have about the Polesotechnic League and the Terran Empire and all written by Poul Anderson, not as a franchise.

There are only two ways that this could have happened. Either Anderson would have had to have devoted his entire working life to this one series, like Tolkien with Middle Earth, or he would have had to have lived for two or three times as long. However, if life were to be extended for as long as that, then would anyone spend that amount of time doing the same kind of work?

Two other future histories are relevant:

James Blish's Okies do spend centuries flying around the galaxy doing exactly the same jobs - Mayor, city manager, astronomer, policeman etc;

in Larry Niven's Known Space History, a man who has had a normal-length career on Earth goes in cold sleep to an extra-solar colony where he will begin a new career in a different profession.

Right on, Niven's character.