How do other pretenders override my Dominion?

[PhilD]

I would also like to know how the cascading effect works.

In solo games, I typically will have temples in every single province, and, as a result, all my "internal" provinces have a +10 dominion.

When controlling most of the map, this should result in a huge amount of "dominion pressure" if the cascading effect was perfect and long-range (that is, if a temple check resulted in a 1-point dominion increase that moved around until it found some place to take effect).