I did a lot of experimenting on this in the course of developing "my" bowling style. I tried several things (e. g. spare system through moving the feet and target), but it boiled down to some simple standard solutions that blindly work:
10 pin: polyester ball, stand 30 with right shoe tip, straight across 16th at the arrows
6 pin: stand 28, rest same
7 pin: strike ball, move feet 9 boards right, same target as strike (1-2 boards to the left if oil is long)
4 pin: same, just feet 7 boards to the right.
I tried left-side spares with a polyester across 4th arrow, but it was too erratic and I was not able to improve on this despite dedicated training. So I switched to the strike ball/line approach, and this works much better.
The mantal cahrm is that I know this works blindly. If I miss, it is an executional flaw and my 10 pin conversion rate is about 90%.
Splits and multiple pin spares are converted dindivisually, e. g. 3-6-10 with a polyester standing at 20 playing straight up 13th board.
Normally I just make sure to hit the pin closest to the foul line first and pray for ricochet effects - got a 2-4-8-10 through this, and also a Greek Church some time ago.
I can see the benefit of having one starting point for all spares - you always have the same view and just march "towards" different targets. If it works, fine. I am sure I could not cope with it, since I tend to walk rather straight/up the boards and have huge problems when I have to slope across the approach. I guess that's what made the left-sided spares difficult for me.
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DizzyFugu - Reporting from Germany
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