Update src/expressions/operator-expr.md

Co-authored-by: Ralf Jung <[email protected]>

Author: udoprog

src/expressions/operator-expr.md

@@ -495,8 +495,6 @@ assert_eq!(values[1], 3);
 - If `T` is unsized and `U` is sized, the cast discards all metadata that
   completes the wide pointer `T` and produces a thin pointer `U` consisting
   of the data part of the unsized pointer.
-- Otherwise a cast from `T` to `U` produces a value identical to the original
-  pointer.
 
 ## Assignment expressions