With putting the resistor as close as you can to the actual grid you are effectively improving the performance of the low pass filter the tube forms.
The grid stopper combines with the Miller capacitance of the tube to work a low pass filter. The filter is used to block unwanted high frequencies but I suppose putting the resistor closer to the tube could somehow limit grid current.
If you want to keep the output tube’s grid wires short and mount the resistor close check out Trinity’s Plexi Brown (white wires)
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