Not to mention the basic issue of... needing to plug in and hook up the empeg for something as simple as tuning a guitar is going rather overboard.

Yes, it is. But then, my empeg is always plugged in and hooked up anyway -- it hasn't even been installed in my car yet, and I've had it for over a year, now.

It'd be like heating up the big oven just to make a cup of instant coffee.

I have no issues with doing that. I don't own a microwave. The microweave may be faster and easier, but sometimes doing things the slow difficult way brings more satisfaction.