Yes, p2pool's sharechain does in effect do the thing I'm proposing here. However, it also does things that are not really needed in my opinion. P2Pool uses the sharechain is to synchronize the coinbase transactions for every miner mining on P2Pool. For this, it uses a payment method called PPLNS. The protocol I'm describing here does not need a payment method.
Semantics: if you send shares promising a percentage cut from your work with a coinbase allocating n% to an address there is a payment method and it's called proportional. To reduce variance people will want to be connected to as many other miners as possible leading to a protocol to establish new reciprocities. Given that the allocation is proportional, miners will have the opportunity to hop.