Robert P. Pula, my teacher, co-worker and dear friend probably qualifies as the most important post-Korzybski scholar and teacher of GS I have known. Here is a brief (three-page) handout, undated but probably from some time in the 1970s, where he succinctly answers the question, "What 'is' General-Semantics?" Worth your time to download and study.
"What 'Is' General Semantics?"
"What 'Is' General Semantics?"
