Add optimality note: exhaustive enumeration confirms magnitude 2 is minimum

README.md

@@ -49,6 +49,10 @@ NOR is OR with inverted output. It's also NOT extended to two inputs: NOR(x,x) =
 | Bias | 0 |
 | Total | 3 parameters |
 
+## Optimality
+
+Exhaustive enumeration of all 7 weight configurations at magnitudes 0-2 confirms this circuit is **already at minimum magnitude (2)**. There is exactly one valid configuration at magnitude 2, and no valid configurations exist below it.
+
 ## Functional Completeness
 
 Like NAND, NOR can build any Boolean function: