From BRCS 3,5:
"A mage can only forge ley lines from a province in which he holds a source (the initial province), but the mage does not have to have a source in the terminal province to which the ley line connects. Ley lines can be forged over any overland distance. A ley line cannot extend over more than 150 miles of water."

It's a different solution than original BRCS.

1. Why a mage does not have to have a source in the terminal province to which the ley line connects?
Doubt: Can Rhoubhe connect his Rhoubhe province with City of Anuire and raze it by Raze realm spell (I assume he choose a time, when Dosiere & Co. have no RP)?

2. Why Ley lines can be forged over any overland distance?
Can I connect a Taeghas and Vosgaard with single Ley Line?
Doubt: There will be a mess of crossing ley lines on the map.

3. Why a ley line cannot extend over more than 150 miles of water?
Why I can connect unlimited (as I understood) overland distances and i can't connect unlimited water distances?
Doubt: Why there are no sea Sources? Sea is wildest and untouched by civilization area than many other terrains?

Thanks for help.