Blomdahl,
4th shot at 6:20. The diagram really emphasis how the cb angle coming off of the long rails vs. the end rails is quite different. The angle appears to be changing quite a bit. I have been aware of this when watching matches, at least it appears to happen. I do not think pocket billiard cushions/tables do this! correct me if I am wrong!
Excluding Diamond tables, I do not know how those cushions react. But a normal GC. Whitey