Are you deaf? All they have to do is employ minfee.
Lol, this is how it is working now. If you want to
do transaction add you transaction into block then increase fee.
Edit:
I do not understand why do we need to increase block size if we want to "employ minfee".
Let's try to "employ minfee" and if they raise too high then we will increase block size to reduce them.
what i'm saying is that even with no limit the pool operators have the ability to pick and choose what tx's go into blocks thus limiting size and they can adjust the minfee that determines the size of their mempools. all this is based on their own internal proprietary data and analysis of the network along with the feedback they get from user fees. this should allow them to protect themselves and the network which they have every reason to want to protect since it is their source of profitability and they're not about to screw it up for some spammer.