It all depends on other factors. For someone with 400+rpm and medium speed on normal lane conditions, 60 degrees of axis rotation could be great, whereas take that same 60 degrees and put it with someone who has under 200 rpm, throws it fast and bowls on medium/heavy conditions, it will be horrible.
I know that sounds like an a-hole answer but there really is no such thing as ideal axis rotation. It's kind of like saying, if x + y + z + a + b = Perfect, then what value of x would equal perfect?
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- Andy