GE might and magic site bonus

[alexti]

Looking at the effects site bonus has on the global enchantnent I've noticed few strange things. Without bonus site
Code:

---

{might}={total gems in spell} - {required gems} + {caster's magic level in the required path}

---

But how {might} is calculated, if there's a bonus? Surprisingly, it seems to be
Code:

---

max(0,{total gems in spell} - {required gems}) + {caster's magic level in the required path}

---

At the first look it seems wrong. First of all bonus doesn't appear in the formula. It appears indirectly though, because the minimal value of
Code:

---

{total gems in spell} >= {required gems}*(100-{bonus})/100

---

Consequently, any value of total gems between {required gems}*(100-{bonus})/100 and {required gems} produces exactly the same result (equal to caster's magic level in the required path)

It would seem more logical if the formula was
Code:

---

100*{total gems in spell}/(100-{bonus}) - {required gems} + {caster's magic level in the required path}

---

However, on the second look, the way it currently works is probably better, because if the formula was as in above, even something as costly as Astral Nexus, if cast in province with 30% bonus with maximum gems (999) would be:
100*999/70 - 150 + 8 = 1285. That would be very hard to overcome or dispel unless from the province with the bonus. Maximal dispel power in the regular province would be 999-30+3=972 (plus whatever exta levels mage has). Even at lower casting powers, those without the site bonus would be at significant disadvantage.

Because of that, the site with the right bonus would have heavy impact on the game (some sites, for example with construction or blood summonning bonuses already have a large impact).

Also, I wonder what are exact rolls made in dispelling and overcoming of GE?