Wrong, many innocent users are caught up with payments blocked.
Second, all pools should pay for mined blocks and triplemining is not doing that. Therefore creating a lot of trouble for innocent miners which at anytime and by surprise could have their payments for mined blocks appropriated by the operator. No pool should block payments for mined work which has already been converted into coins. Period.
Third, as previously said, I will agree on blocking bootnets from mining or just closing the "suspected" botnet accounts, but if you read carefully, the operator is not doing that.
It's just common sense what is defended here.