Well I currently see myself as a tweener and still play as a down and in player when I need it. Which can be an advantage as you have less of the arcing and a more direct angle to the pocket. With down and in you don't have to put much on it if you have a reactive ball. I used to just throw mine with very little finger lift and it would go straight down and then angle into the pocket. I have since learned to use the finger lift and have been able to get a little more reaction. One of the guys on my league team bowls with a plastic ball and throws dead straight and averages around 160.
My advice would be to learn to adjust, I have had nights in my league where it was almost a shark like pattern and I couldn't get the hook like I have been getting weeks before so I threw a more direct down and in instead of fighting the hook. My team did very well as the other team decided to fight the hook for 3 games instead of adjusting.
As far as targetting when I throw down and in I stand around 2nd dot and throw 2nd arrow. When I play a bit more hook I stand a tad more left from the 2nd dot closer to the 3rd dot, but still throw 2nd arrow. When throwing more hook I normally drop my shoulder a bit, I forget exactly how dropping the shoulder helps but I think someone probably has an answer. I just find it helps me with getting a little bit more revs on the ball.
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