My controller failed about a week ago

, bought a new unit and hey presto.
From what I can make out the bike starts up at 100% pump efficiency and then cuts back to 80%?
Is this purely to prevent filter changes? Why not just fit the fuel filter outside the tank?
I am in the process of stripping the old controller for the connectors to rig up a bypass in case of another failure.
There was zero corrosion by the way, even under the resin on the controller.