Once this catches your eye, you'll notice that he does it *all* *the* *time*
In the SF, Bunting was on 280 and Littler was yet again on 170. The match was almost over (6-1, 1-1 iirc) and so Bunting threw 60-50-60. As Littler went up he was having trouble controlling his smile. He threw the 60-60-50, and then the two of them shared their moment.
And I think this is one of his weapons — he makes losing to him fun, his opponents get to join in with his playfulness. There's a famous clip of him going Tops Tops Tops for a 120 finish against Peter Wright. What the clip failed to include is that a couple of legs earlier Wright had thrown Tops Tops for an 80 finish. Littler's 120 was like saying, nice, but how this? Hence Wright spluttering into his drink as he watched.
I forget at which point it was on Friday, I think somewhere in the middle, but Littler went Inner Bull, Double 10 for a 70 finish. What that communicated to MvG, heaven knows.