This track used to be more common with crankers than with tweeners. In fact I have read from a coach or two that this is the preferred track with crankers.
The advantages and disadvantages are dependent on your point of view and ball speed. It is generally an earlier rolling release, as it is often, but not always caused by lifting up without turning your thumb or rotating your fingers. Most times, there is little rotation by the bowler.
On good amounts of oil, this can be an advantage - early roll. On lesser amounts of oil without good ball speed, it is a liability.
In and of itself, it is neither a good thing nor a bad thing. It just is.
However it is still unusual and your driller should know your PAP; so he can drill balls properly.
--------------------
"None are so blind as those who will not see."
