hi beneath_the_sur,
the position of the 3 balls on the pic is very different than the position on your vid .
One of the problems you'll notice in the carom game is than a verrrry small difference of position for one ball (especially on the CB-OB1 couple) can mean a completely different shot
Another big problem of the carom game is the particular memory process required , to memorize the right, exact, positions ( & angles) of the 3 balls for each technical shots.
It is not so easy, it takes a lot of time , and we aren't equal. Some humans do acquire this particular memory very quickly , some need a lot of time, some years . Some will never aquire it, and that's a major fact in their stop of progression in this game.
But whatever so many ppl may claim , this particular memory process is THE basic difficulty of carom. here is the difference between advanced players and masters. You can train 18 hours/day if you want/can, but it is a waste of time of you pratice false positions !!!!
false/bad positions -> waste of freetime/practice.
The key of game progression isn't in the shots theory or in the stroke , the key is to memorize with accuracy the right, exact balls positions for all the particular , classical/easy shots. Then , and only then, you'll be able to choose the shot you wanna play. You have to concentrate your pratice on the easy shots, the playable shots. IMHO It is a waste of free time to pratice a lot on hard or impossible shots. they are hard or impossible for everybody. What you should concentrate to do is, to not miss the easy shots, to achieve them at a verrrry high % everytime , everywhere.
(i know that this advice can sound unusual . It took me 5 years to reach a general average of 10.0 at straight rails on 100 points , then 5 years more to go from a general average of 10.0 to >=20.0 on 200 points big corners tournaments . And i'm still learning the game, i know I am still a beginner , i have a lot of respect for masters & champions, i know that all i can do is to dream to their level. Carom is the school of humility.
Blombdahl , Ceulemans, Mercx , Dielis, Jaspers were all at >>100.00 general average at straight rail and 50 at balkline in national & international tournaments when they really started to play 3 cushion. That's a fact . About the koreans (Korea is an exception) , i dunno . But IMHO Cho & the other koreans can play real good at the small discipline ... )
3 cushion is so hard than at first , best is to try to learn to master the basis of carom , aka straight rail. When ppl don't do that, they are condamned to stay at a medium level, like 0.700 on 30 points , they will dream all their life to reach a general average of >0.9 . There isn't any magic solution : the stronger to straight rail you are, the bigger potential you have at 3 cushion . Don't believe me ? "rendez-vous" in 10 years

!!
When you want to pratice a particular shot, i would suggest you to use white taylor chalk to mark the balls position. That's the best way to be 100% sure than you'll replay the exact same shot.
My 2d suggestion would be , since you seems to begin the carom disciplines, to concentrate your efforts at first to straight rail .
Try to reach a general average of >=5.00 on a 100 points distance at straight rail (small corners) , then you will be able to progress faster at 3 cushion. 5.00 isn't so easy, it means 20 innings at max , on each games. small corners, don't even think to the big corners.
I know, i know, straight rail is boring, it can sound useless to so many players , but some things are sure :
-almost all the 3 cushion champions were, primary , when they were younger, straight rail/balkline champions. The basis of the carom disciplines is straight rail.
- to acquire this particular memory process isn't easy , but it is absolutly needed. straight rail is the king of game when it comes to positions memory , because positions memory is the key to this game.
a quick question about your thread : is it a position related to a 3 cushion point/game, or is it related to straight rail ?