Ground hook up in GGG Reverb project

[disorder]

http://www.generalguitargadgets.com/pdf/ggg_verb_sc.pdf

Notice how the 5V regulator ground only connects to the Belton bricks "Ve" or POWER GROUND connection (pin 2 on reverb connector) and to the negative lead of a 47uF whose other end connects to the 9V in. Why doesn't the regulator ground connect straight to the normal ground bus of the circuit? Is there an advantage to this?

[armdnrdy]

One pin of the brick is power ground and the other is signal ground.

If I recall correctly...they are connected in the brick.

The advantage is...it keeps the two grounds separate....less noise and digital artifacts.