+ *
+ * Determines whether the CompositeBlock applies to a right by checking
+ * whether the original blocks apply to that right. Each block can report
+ * true (applies), false (does not apply) or null (unsure). Then:
+ * - If any original blocks apply, this block applies
+ * - If no original blocks apply but any are unsure, this block is unsure
+ * - If all blocks do not apply, this block does not apply