The problem with the thrice-damned R4 and R7 is that they prevent the USBTiny from dragging the data lines high/low reliably if there is any other load on the ATMega's pins. Jumpering them allows the USBTiny to force the pins high/low even with other crud attached.
The power control is handled by the jumper in the USBTiny and has nothing to do with R4/R7.
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Persephone: DL R+W+B C 7 X L W C++ I++ T+ A E H++ S+ V-- F+ Q P B PA+ PL
Aldebaran: DM Rt H 5 Y L- W+ C+ I++ T++ A+++ E H++ S+ V+ F++ Q+ P B++ PA- PL--