Thanks for the reply.
Well, that is good news.
Also, I should mention in case anyone tries it...
If the UNO is unplugged from the computer, it has no power on it and tends to drag down the reset line, even with a 10k pull up on the Atmega328's reset pin, so I had to disconnect the reset line from the UNO to get the breadboard circuit working when the UNO is powered off.
It may even require powering off the ATmega328's circuit to get the reset to work again... not sure why, just something I noticed.