Balearic slinging competition is just that.

It is not a true measure of slinging ability, just ability in that particular competition and within it's parameters.

It would be like saying "John Smith won the 25m pistol competition with a 1911, so he is the best shooter in the world"

Just wanted to clear that up… 

Sorry but i wasn't able to record a 25m challenge video, however i was able to record a short video, of me slinging for power with tennis balls in a gym. here's the link: https://www.youtube.com/watch?v=ktDQlzlIS6c&feature=youtu.be

i'm facing backwards so that i know where the sling is, so that i can get in sync with it, that way i can lift my leg at the right time, and get the maximum power, and the spinning is also for power, because of static and kinetic friction, kinetic friction is less than static friction, so that means that when a sling is spinning, it is easier to move to a higher speed, than when you would start from no spin. 
also yes i have tried figure eight, in fact i used to use that all the time, and i still do, but for power, this style has way more then any other style that i've seen, for a short sling. since this style ends with the same hand position it has the same accuracy as the original figure eight, just more power because you aren't starting from standing still, so it's easier to get the ammo moving. again this video was not made for accuracy, it was made for power, so i get your points but, the problem is, is that you haven't seen this styles accuracy. 

thanks Thearos, that means a lot. 

Blowgunman123, at that distance, with a proper fig-8 and tennis balls, you should be able to put them all into the blue square in front of you.

You are facing away from the target, spinning your sling rapidly, and then turning to look at the last minute, slowing your rotation to near stall speed, and then rotating into a normal fig-8.

Try taking your left arm and extending it toward the target, drop the pouch and keep it pointing at the target until its time to bring your left elbow down for power.

You have the basic mechanics, but all that spinning and facing away from the target is not an advantage, its a hinderance.

Just my .02…take it for what its worth.

I'd say the facing away is to get the longest trajectory on the sling development (a characteristic of power shots), and the spinning is just to have the sling in movement before the final release so as not to have inertia to overcome. The idea here is to use the power shot to get flat trajectory and hence accuracy; the problem is that the body spin through 180 degrees, if not sufficiently controlled, will lead to inconsistencies in release orientation (and hence shot dispersion).

Jaegoor teaches to keep feet firm, so to pare down movement to body only. If you wish to keep the looking away (and hence the long development), you might look at planing your feet firm, and transforming the turn itself into something that is a bit snappier, but well focussed and controlled.

Good luck !

here's the video the first shot was me Slinging for power, the second was for accuracy. https://www.youtube.com/watch?v=RB_e4Q5yHLY&feature=youtu.be

came on!! challenge!!!  25m watermelon, buckets, or zombies! jejej
nice video. I think you move alot your body, think the moviment with your Hips is the most important for power.