Doesn't that already exist?
log in to p2pool and append /SHARECHAINTARGET+WORK_TARGET
e.g.
./cgminer -o something.pool.com:9332 -u mineruser/5000+16 -p none
that will return 5000 difficulty work to the share chain, and it will only serve 16 difficulty work (instead of "1")
Not sure if you'd know but ...
Seems to me there's some mileage in setting the difficulty to higher than the defaults if only to reduce network latency? I've started tinkering around and setting to minername/512+1 and it seems that 'Bitcoind GetBlockTemplate Latency' has reduced slightly since then.
Since getting that latency average down as low as possible is one of the only things you can do to improve p2pool returns (afaik), this seems to be an overlooked tweak?
I might also be being a bit dumb, but what's the point of setting the difficulty higher than the current valid accepted share difficulty? It's at 1300 at the moment for example. So any share submitted over 1300 should count.
And finally .. me also not understanding something (yes I have tried to!), if I've set 512+1, then why is it still returning 1/1 to 511/1 difficulty shares to the pool? Or have I got that the wrong way round?
Basically I'm puzzled by the difficulty settings and there ain't much documentation on it that I can find.
PS. Note to Litecoin miners. If it's giving you so much grief on p2pool, why not forget Litecoin and concentrate on Bitcoin? Seems to me that if you want BTC to retain value for all the BTC you mine, then sticking with BTC is the way to go long term rather than supporting a slightly less secure competitor for what basically seems to be greed.
PPS. Note to people freaking out because p2pool throws some errors and pauses a while to figure it out. Stop staring at the p2pool screen! I've only seen pauses like that near the initial startup while p2pool is easing in to the network. I guess it may happen while I'm asleep after running for hours, but if it does, it recovers, it goes on churning away, I maybe loose a few minutes. I've never yet checked it the next morning to find it's died, it's always happily churning away.