EDIT: Patched on Oct 1, this method no longer works for large amounts of points.
Overview: On the new island, frogs used to the concept of double tapping on the old island were struggling to get high scores - they just weren't cutting it in the effort to reach over 10 million. What would obviously be a 140K double gap turned to a gap shot that fell obviously short of what a double tap would normally be. Other attempts to double tap normally resulted in only 50% of their score, worse than getting a gap shot through gaps that already existed. Other options were needed.
Within a few days after reaching the island, even causal players have been able to even top scores that professionals had extreme difficulty reaching. Something was up.
A careful study of gap shot techniques revealed that points were best accumulated not by how steady you can keep your hands when firing through narrow gaps, but based on the size of the gap. Guess they were compensating for something.
The technique was named 'Extra Large Gap Shots' due to using a large gap.
To Pull Off: Get a ball very close to the skull. Clear out as many balls as possible between the last ball and the start (while making sure that last ball doesn't slide back). Make gap shots as usual - any gap shot bonus that passes through that large gap is amplified by several factors, making multi-million scores seem trivial in just a few shots.
On some boards this can be quite difficult to pull off, with the level of difficulty similar to trying to maintain a continuous double gap, only the latter scores significantly less and really needs to be adjusted.
Score: If you have a large gap about the size of the entire curve (or a 50-ball gap), each gap shot that passed through it will be worth around 750K at 9x. The value of those gaps will decrease steadily the smaller the gap is (10% less every three balls) until the gap is only half the size of the curve, which the bonus will be a measly 500 points until the gap's five balls wide, which then will steadily increase up to 65K.
Tips: Candy Lei can be very helpful in reducing the amount of randomness in balls, making it easier to clear them.