Hello Ernst,
If a planet is db or combust (low chesta bala), then its manifesting potential is not there. If a planet is very weak in dig bala, can we also say its manifesting potential is non existent?
Yes, but it's not as important as dignity. dignity is the most important factor for manifesting potential - the uccha, chestha dig, it has to do with auspicsious quantity. If they are high, anything manifested will give MORE of that good. If they are low, less of that good. and on the other hand, if the planet is indicating something troubling, it will give less if those are high, more if they are low. These things are Quantity of good and bad that the planet can give based on what it is giving.
Jaimini gives planets in Ex srimantha if in Pada or UpaPada. What about grahas in OH sign? Like Ma in Aries but in the Pada? That would have to be considered more auspicious?