It isn't, as that sort of thing was a well-known thing that was in computer textbooks of the time. What that article says about the scheduler is rubbish, by the way. Dynamically adjusting priorities according to recent CPU use was also a standard textbook notion. It isn't "magic".
For example: A contemporary textbook to that 1991 BYTE article is H. M .Deitel's Operating Systems, 2nd Edition, published in 1990. It deals with feedback scheduling and things like multilevel queues and dynamic priority adjustement in chapter 10. And OS/2 (1.x) including its scheduler is a case study in chapter 23.
For example: A contemporary textbook to that 1991 BYTE article is H. M .Deitel's Operating Systems, 2nd Edition, published in 1990. It deals with feedback scheduling and things like multilevel queues and dynamic priority adjustement in chapter 10. And OS/2 (1.x) including its scheduler is a case study in chapter 23.