Even more years ago the mechanic would hand signal or headset call rotation when he saw the fan rotate, back in 1974 a BOAC flight was cancelled due the crew had no N2 reading, they missed the fact that for the N1 to rotate the N2 had to be good. Whether it is a twin spool or triple positive N1 rotation should be a good practice; of course all is left to the FADEC on modern jets.