code: boolean corralIfNeeded(Collection<Unit> working) {
          if (isRecoverable()
                  && si.corralled() != null) {
              activeGuts = si.corralled();
              setWrap(working, working);
              return isAttemptingCorral = true;
          }
          return isAttemptingCorral = false;
      }
docs: If it meets the conditions for corralling, install the corralled wrap
  @return true is the corralled wrap was installed