Because it will almost certainly go KABOOM.
Intimately mixed fuels and oxidizers are pretty much indistinguishable from explosives, and in particular, LOX intimately mixed with flammable hydrocarbons is an incredibly touchy explosive thatwildly dangerous -- rather than being something you can handle, it tends to be set off by shock, vibration, or allegedly even havingadiabatic compression that can be caused by closing or opening a light shined at itvalve. There is no chance you could get it through
Perhaps the turbopump. Let alone load upmost infamous LOX-hydrocarbon fuel mixture was LOX and liquid methane (which are perfectly miscible), discussed in Clarke's Ignition -- it was supposed to act as a rocket withmonopropellant as you are describing, but was allegedly (though disputedly) so touchy it could be detonated with a bright light.
(This issue destroyed At least one of the Bell X-1 rocket plane usingplanes was destroyed when LOX in contact with a much less flammable hydrocarbon that wasn't thoroughly mixed like thatoil-impregnated leather gasket detonated due to vibration. A bulk mixture of LOX and kerosene fuel is far worse -- it surely could not survive passing through a turbopump, and there would be little to stop the detonation in the combustion chamber racing up through the fuel lines and setting off the whole tank. (Detonation arrestors exist, but they don't save your engine and fuel lines from being rapidly disassembled, nor do they protect your tanks from shrapnel, as Clarke learned).
Additionally, RP-1 is going to freeze at LOX temperature. The interaction of small particles of hydrocarbon probably won't help matters.