Hi guys, I'm not sure if I'm in the right board, but you folks seem to know something about MPM travel.

Somebody knows when a HIP (higher intermediate point) triggers a higher fare on MPM (maximum permitted miles) travel?

I suspect that this happens if you do a stopover (let's assume there are no stopover restictions in the fare) on a HIP rather than just connecting in a HIP. Could that be the case?
On my trip, I'm considering to do something like
A-B-C-...-Z
The A-Z fare is much lower than the B-Z fare (and the A-C fare is higher than A-Z, too). So plenty of possibilities to get caught by the HIP rule. How should I plan? Just avoid to stay more than 24 hours (stopover on an international ticket) at those HIP-dangerous points? Or do I need to avoid those points completely?

There is one more point that may be of importance on the trip I'm planning to do. What happens if you do something like
A-...-L-M-L-...-Z
within the trip, assuming that you stay less than 24 hours in M (again no stopover on an international tix)? Could that trigger the HIP rule? (I already found out that my fare from A-Z is lower than A-M)

Thank's, folks! Any help appreciated!