Frank Heckenbach wrote:
OTOH, Adriaan's problem is not one of strange rules (AFAIK), but a simple performance problem that can probably be solved, or at least alleviated, without long discussions (or could have ... ;-), and with less implementation work.
That's why I initially asked whther you are interested in the general solution of this issue (and have the time and willingness to resolve the issues in discussions, and then do the implementation, I should have added)? As you replied: "ATM I would prefer to think more before implementing general solution.", I took this for a no, so I assumed we were talking about the quick fix only.
As I wrote I would like to have a fix which is part of a general solution. But I must admit that ATM I do not see a really quick fix. I intend to go back to this problem in few weeks, but I you want to do something in the meantime just go on.