Check out this link: http://www.freewebs.com/valvewizard2/Grounding.html
It explains the issues with grounding very well. The 2stroke is a simple circuit and is forgiving when it comes to grounding. That said, there is still opportunities to create more noise (hum) or reduce it. The 2stroke can be very quiet, so building to that goal makes sense. When reading the linked article, pay particular attention to the sections on ground loops and star grounding.
These concepts are true for all electronics, not just tube amps, and can serve you well to understand when trying to sus out a loud hum in a PA system or reducing 60 cycle noise in a single coil pickup equipped guitar. Following DH’s grounding scheme from the book works great.
In the “building a 2stroke head” forum topic here on the TAN site, I mentioned my plans for grounding and it worked out very well. If you are using a grounding plate, per the original design, or attaching grounds to the pot cases, be sure to use a soldering iron that is powerful enough for the job, I would recommend 60w, minimum.