1. There is a trigger, that is just above Spongebob's head when on ground level, which counts each jump to annoy Squidward. There is no cooldown between each activation cycle, you simply need to enter and exit the zone. And it just so happens that you can weave in and out of this trigger every other frame by standing on the lip of the tiki.
2. DCB stands for "Displacement Cruise Boost" and is essentially no different from a regular CB mechanically. A CB stores your Bubble Bowl(BB) momentum by interrupting the animation with Cruise Bubble. This requires touching a wall (unless you are on flat ground and have no momentum). The amount of speed a BB has is solely determined by the distance Spongebob moved on the previous frame. Regular walking speed is 5, and the lowest possible BB speed (and therefore slowest CB speed) is ~0.6. A DCB is simply a CB where the technique is executed on the frame of a large displacement. Commonly this is done using the Bubble Ball displacement, but it can also be done through Spongeball displacement storage (
https://www.youtube.com/watch?v=7jknPNcLWOM) and presumably tiki or enemy displacement (I don't have videos of this).
If you've ever wondered why non-TAS CB takes two iterations to get "full speed", this is why. The second execution is done while holding straight left or right, and the 5 speed gained from walking left/right is the speed which ends up being stored. "Instant Cruise Boost" (ICB) is also the same mechanic, but it is done by aligning Spongebob's position a perfect distance away from a wall, whereby the travel time to the wall is a distance 5 units higher than your base speed, such that the momentum it stacks +5 units (optimally) each time.
Edit: And one last thing! Having too much speed can cause a LBowl rather than a CB input. Currently, I have not managed to get higher than 27 speed with DCB. Anything more seems to always clip and therefore not meet the aforementioned "touching a wall" requirement.
3. Thanks~ ^_^