Remove inappropriate 'existing behaviour' reference; simplify

Author: ntrel

spec/expression.dd

@@ -167,10 +167,8 @@ $(GNAME ConditionalExpression):
 
     $(P $(B Note:)
         When a conditional expression is the left operand of
-        an $(RELATIVE_LINK2 assign_expressions, assign expression), they would be
-        parsed as an assignment to $(I the result) of the conditional. This
-        has now been deprecated. To preserve the existing behaviour, add
-        parentheses for the conditional without including the assignment:
+        an $(RELATIVE_LINK2 assign_expressions, assign expression), 
+        parentheses are required for disambiguation:
     )
     ---
     bool test;