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The Full Pay-per-Share (FPPS) approach, created by BTC.com team, aims to benefit miners from the high transaction fee. It will calculate a standard transaction fee within a certain period，add it into the block rewards (12.5 BTC every block for now) and then distribute the whole to miners according to PPS mode.
This method keeps advantages of PPS and pay more to miners by sharing the transaction fee.
Well, you are still "saying" you are charging a 4% fee, 4 times higher than some PPLNS pools - so your reply is at best misleading.
It is also false, since as you say (marked in bold) you are paying PPS at the moment - so at the moment that's at least a 10% fee, not a 4% fee.
You have also directly entered into the extremely risky area of high PPS reward.
Meni Rosenfeld has a document about that ... you should read up about it:
https://bitcoil.co.il/pool_analysis.pdf