No, that buss wire is only for the more sensitive parts of the amp - ie the preamp and PI. The power amp and power supply should be grounded to a single "star ground" connection to the chassis, at the far opposite end from the input jacks and preamp, labeled as the "power grounding point" in the Mojotone layout. It should also be kept separate from the AC Safety Grounding point.
There should be no connection between the power grounding point and the preamp/PI ground buss wire, except through the chassis.
The filter caps supplying the preamp and PI stages should be grounded to the buss wire, with each stage's filter cap grounded immediately adjacent to where the stage's cathode resistor+cap are grounded, to help prevent ground currents crossing between stages.
I hope that made some sense...