code: public boolean isDuplicateDigest() {
  		if (!isRevisitDigest()) return false;
  		CaptureSearchResult orig = getDuplicatePayload();
  		if (orig != null && orig.isRobotFlagSet(CaptureSearchResult.CAPTURE_ROBOT_BLOCKED))
  			return false;
  		return true;
  	}
docs: whether this capture is a re-fetch of previously archived capture
  (<i>revisit</i>), detected by content's digest, and replay of
  that previous capture is not blocked.
  <p>1.8.1 2014-10-02 behavior change. This method now returns
  {@code false} even for revisits, if the original capture
  is blocked. Use #isRevisitDigest() for old behavior.</p>
  @return {@code true} if revisit