How do other pretenders override my Dominion?

[LintMan]

Originally posted by Graeme Dice:
Every time a successful temple check occurs, and the province is at maximum dominion, it is likely that the dominion will spread to a neighbouring province. If you don't have enough temples to counteract this, then you will lose dominion in your provinces.

Does the temple check spread have a cascade effect? (ie: if the temple check succeeds, but surrounding provinces are already at max, will it try to spread to provinces further away?)

If it doesn't cascade, it's strange that his own dominion would fade so dramatically if he destroyed all/most the surrounding temples.

Does Pythium have stealth priests? Of perhaps stealthy priests from another race (Marignon?) had infiltrated?

Or maybe Pythium had that "restless followers" theme? I think that makes dominion spread to surrounding provinces independently of temple checks. (I'm curious about how that works, exactly.)