TSAB - I have read all of this. What is missing for me is actual pattern analysis of enough patterns to arrive at a statistical answer.
Jim - if inward acceleration was the root cause, we would spend our time discussing choke taper, not constriction. We all pretty much agree that constriction is way and gone the most important factor.
In theory, a parallel will build pressure in the shot column due to flow friction losses. This explains why a long parallel will reduce constriction effectiveness and supports the theory that reducing pressure within the shot column is the key to delaying pattern bloom. However, it does not support any benefit from a parallel. Data will tell the tail!
