My experience with him is firstly through Tcl, which I like more than he does now (time for a TIP: "-jo" switch to [unset] which removes complaint to unset non-existent variables), and his book on it, and various papers. His work is at once both powerful and humble. Note in  how he without much emotion he suggests how Tcl came to be less prominent, and how even at Tcl's height, he explained without ego why it was there, and how it would leave. His papers on threads and comments on performance and testing are also lovely reads. I encourage any developer or architect to read or re-read them.
 https://vanderburg.org/old_pages/Tcl/war/0009.html (This is The Law, and it is good.)