No, this is not about punching the glass – a dangerous approach. But it is a two-fisted approach to holding glass to break it.
For scores with significant, but not necessarily equal, amounts of glass on each side of the score this is a quick simple approach to breaking glass. After scoring, raise one edge of the glass and put your fingers under the glass on each side of the score. Curl you fingers into your palm, and put your thumbs on top of the glass. Turn your wrists outward and the glass will break cleanly.
With practice, the initial part of a curved score can be run by applying light pressure. Then you can turn the glass around and run the score from the other end to the opened score. This avoids lots of tapping and gives clean edges to the cut glass. It is just as simple as using cut running pliers and avoids the flare often associated with using cut running pliers.
This technique works best with glass that has at least 50mm each side of the score and on gently curved lines. For tight curves and narrow strips other methods need to be used.