Oh dear.
Look, MJ is cool and all, but don't go copying circuits wholesale if you can't read Japanese.
JB was wrong about the circuit. The red "X" he marked to indicate what he thought was an incorrect connection is itself wrong. The circuit is correct as originally drawn, the connection does not short to ground, it appears to set the gain, connected as it does to the "MC gain switch".
The left and right halves of the circuit are maked "MC head amp" and "Phono EQ amp" respectively. The RIAA network is right there in the circuit, bottom right, where is says "NF型EQネットワーク". The key point here is the MC/MM switch only engages the low impedance "grounded grid" input stage when MC cartridge is selected, MM carts are routed directly to the second, high impedance second stage.
Don't use the "MC head amp" circuit with a MM cart, you will be completely screwed...