Son of Screamer variant schematics

[mordechai]

Looking at Orman's "Son of Screamer" circuit on two different sites -- beavis audio and RG's Tubescreamer article on AMZ -- there are some differences and I would value some explanation/clarification:

1. On RG's schematic, the power section seems more complex.  There is a series resistor of unspecified value coming off the battery line, and there are two 47uF electrolytics.  In the Beavis version, these items are missing.

2.  In RG's schematic, the voltage dividing resistors are valued at 10K; on the Beavis version, they are 100K.

What accounts for these differences, and what purpose is served by the unspecified series resistor in RG's version that is absent from the Beavis version?  How does this affect the other component choices in the power section?