I looked at it more closely since the top six keep fees   but via.btc does  give back some of them at the monment.

So  the top five are a no go zero money sense to mine on them.

Viabtc is more complex.  they are  paying more then the block  but not all the fees to the miners.

but the top five simply can not be used.

Kano = okay
ck solo = okay
the other ck = okay
mmpool = okay


nicehash is a no go as the rentals could point to the top five.

I have to study this  but this is a different  50% attack

then block with-holding    it is fucking worse  really bad  truly  will kill btc  while the top pools make more profit doing it then not doing it.

A fix is very important  some say segwit  but I think not.

A simple  jump to 4,000,000 size  blocks would work for now.

or everyone   boycotts those top five.