Mark is not even the best songwriter by means of popularity in comparison with Sir Elton, Sir Paul and another Sirs, by complicity of songs or by means of moving the world like Dylan or Simon or Elton do, he's not the best guitar player in comparison with 999999 guitarists from lists by magazines of the same amount, not the best singer in comparison with Shirley Bassey and tons of other UK and worldwide genius singers, BUT for us he's the number one! And vice versa. Mark's musicians are the best for him just like he's the best for us, that's all.
And Guy seems like 'best of the best', simply because they work together more than even Illsley was in the band. So it means something.