MergeQuery comments not added to the query sent to the database

There is a comment on the existing __toString method that indicates this was by design?

  /**
   * Implements PHP magic __toString method to convert the query to a string.
   *
   * In the degenerate case, there is no string-able query as this operation
   * is potentially two queries.
   *
   * @return string
   *   The prepared query statement.
   */
  public function __toString() {
  }

Yeah, agreed, this feel like it's by design. Closing for now, feel free to reopen this if you feel this is still something we should address.

Thanks!