When searching for a block-chain to use, if the share difficulty is too high, the p2pool client attempts to find an another p2pool sub-pool to use which has a lower share difficulty.
+1, you could set-up max and min share diff in settings and p2pool would search a share-chain that meets the condition
This seems like such a great idea. p2pool would automatically fragment itself into nodes that had overlapping ranges. The problem is that there is no way to enforce which pool someone should be in. If everyone wants to stay in the 100-400 difficulty pool, the feedback mechanism fails when it hits one of those two numbers, and the share clock breaks.