Again, at the velocities involved in interplanetary maneuvers, there are no hard turns; for every day it took you to get to your current velocity, it would take you two days to change your course by 90 degress.
And you do not seem to be taking into account that the intercepting force will be starting with a speed of zero after jumping to the pirate point, and that it takes dozens of hours to multiple days of acceleration to get up to the velocities involved, during which time the fleeing force is still accelerating itself. That's why in all probability that it's going to make little to no difference just how offset the pirate point may or may not be; for all intents and purposes, the speed difference will be so great - and remember that it only needs to be a difference of approximately 100 hexes per Turn along just one vector to count as a high-speed engagement - that the difference in course is only going to determine whether its a head on or crossing high-speed engagement.
If, as I noted earlier, the pirate point is positioned just right and the pursuer has a significant thrust advantage - and I believe the court is still open on whether or not ships can maintain multi-G acceleration for days on end, I've seen posts suggesting either way - to allow them to slowly close the range for a standard engagement, it's going to take multiple days. Also remember that if the pirate point is offset from the fleeing force's course, the pursuing force is going to have to divert part of its thrust to close that gap, thus reducing how much thrust it can devote to simply catching the foe and thus extending the time it'll take. The big problem with all this extended maneuvering is that it takes so much time, days that add up with those that the fleeing force has already used to build up its escape vector, and during that time the fleeing force can quite possibly finish its charging, get outside the KF limit and jump away before the interception can occur.
And let's not forget that the fleeing force is going to do its hardest to ensure that it doesn't go anywhere near pirate points, or even possible pirate points, in the first place. Even assuming that the fleeing force doesn't have enough astronomical data to know precisely where and when pirate points will occur, they'll know enough to predict where the possibilities might occur, and if they're really lazy or smart they can just point straight up or straight down from the plane of the ecliptic and simply not have to worry about pirate points at all.