On Thursday, September 10, 2020 at 6:55:32 AM UTC-6, wrote:
Is this still a good reference today?
.... or is it outdated with much better information in the multitudes of books printed now?


It is still OK, others are better written by glider instructors (Wander Knauff, etc.) :

The handbook is free on-line:

https://www.faa.gov/regulations_poli...ider_handbook/