OptiLoader is separate from the bootloader itself, mostly. You can find it here: https://github.com/WestfW/OptiLoader
OptiLoader runs on the Arduino where you might have run ArduinoISP, and it DOES eliminate the need for the "burn bootloader" step. Assuming a target chip or board is properly wired to the Arduino running optiLoader, it does in fact burn the bootloader into the target automatically on powerup or reset.