In my opinion, several sentences from the comments are doubtful. It's difficult to answer "with numbers" as soon as I don't have any simulation software on hand and "manual counting" would be rather time-consuming, but...
Lets look into 12AX7 datasheet and specifically at "Class A resistance-coupled amplifier" section. Here we can find the standard usage with the following params:
Ub=300V (Cornet 2 Ua=300V)
Rk=900Ohm (Cornet 2 Rk=910Ohm) - the only difference is bypassing the Rk in the datasheet
Rp=100kOhm (Cornet 2 Rp=150kOhm)
Rg=100kOhm (Cornet 2 Rg=47kOhm in the 1st stage, 150k in the 2-nd stage)
Rload=240kOhm (Cornet 2 Rload= from 110kOhm at 20Hz to 16,5kOhm at 20kHz in the 1st stage, from 8 MOhm at 20Hz to 11,5 kOhm at 20kHz in the 2nd stage)
Counted load from datasheet: around 70 kOhm; from Cornet 2: 1st stage 63kOhm to 15kOhm, 2-nd stage 147kOhm to 10,5kOhm.
It seems there is no such catastrophic differences from the datasheet usage in design. The only question left is high-frequency loads. But at the output there is only small amount (-40dB at 20kHz comparing to 20Hz) of high frequencies. Input voltage is 5mV gives us only around 200-250mV (1st stage) of the anode voltage swing total, so linearity is clearly not damaged.
Maybe I'm wrong, but my impression that the output impedance of the stages on AX7 in the design is about 170kOhm. About 2 years ago I counted the value somehow and proved by recounting the RIAA curve.
P.S. By the way - Plate Resistance from the datasheet for General Electric 12AX7 is 80k for 100V Plate Voltage and 62,5k for 250V Plate Voltage (Cornet 2 - around 150V). Unbypassed Rk makes Plate Resistance even lower.