In "Burning the Bootloader" there is no mention of disabling auto-reset on the host Arduino. That caused me confusion for MONTHS.
In "Uploading Using and Arduino Board" there is no mention of resetting the target processor, either automatically by connecting the Reset pin to the Reset pin on the 'beheaded' Arduino, of manually by briefly grounding the reset pin on the target processor.
Since the "Burning the Bootloader" setup can also be used to upload sketches (at least it worked using a Diecimila to program an ATmega168) it would save people a bunch of re-wiring to use that method instead of beheading their Arduino. They won't get two-way serial communication with the target chip but if they don't need it, it saves time.