0% fees and PPLNS earnings. (The tx fee is not paid out to miners for maintaining cost and the bonus for our engineers.)
This is not possible on the existing p2pool share chain. Every p2pool node would have to upgrade(?) to bitmains version.
PPLNS block transaction fees help pay for the pool, INCLUDING the p2pool side. It doesn't mean p2pool side is providing transaction fees.
Sigh - you really need to learn about something before posting.
They've explained it above already, but I'll try it in detail.
Everyone else running p2pool will not allow Bitmain to siphon off the tx fees to an address - since it will break the rules required of the generation transaction in their version, no matter how Bitmain try to do it.
Thus what would happen if Bitmain started mining on the real p2pool, is that their > 51% would be a true > 51% attack and fork the share chain and then be a separate share chain unrelated to the standard p2pool share chain.
I'm not sure of the full ramifications of that, but I suspect it would mean 2 separate p2pools, one running the true p2pool code by forrestv and another running the forked code.
There is of course something worse than that if Bitmain didn't fork the chain and used a valid generation transaction:
p2pool would sudenly overnight be about 10 times bigger so everyone mining would find 1/10 of the shares they are currently finding ... thus it would be pretty much common for most p2pool miners (using the official forrestv code) to rarely if ever get any payouts.
Its you who isn't understanding, mainly because we're all saying similar things.
There are two sides of Antpool:
1) a normal standard, run of the mill pool acting independently (like btcguild, ghash.io)
2) an exotic p2pool 'pool' which is attached to the p2pool share chain.
Pool 1 retains transaction fees. Pool 2 doesn't. Pool 1's transaction fees help pay for SOME of the costs of hosting both pool 1 and pool 2. [next person to quote please cut it down, its too big]