Oh please. "real work" does not mean leaving your tractor sitting in front of the barn running at PTO speed while you go to lunch or shopping. Let alone in front of your house. Fact is, they are not made to do that UNATTENDED and you know it. Yes, you can use them to run a variety of equipment while stationary off the PTO like augers, conveyors, pumps, and even PTO generators. But, they are, obviously, not made to sit there and do that with nobody around. That would be why they have those "wheels" and a "seat" for an operator to sit on. It's also the reason they are called "tractors" and not "stationaries". It is simply the wrong choice to do work like that in that situation. If you need something to run a pump or generator for hours on end with nobody around, you should consider a proper stationary power plant. Obviously, an emergency it could be used to run a pump or a PTO generator, but I wouldn't consider a power outage to be an emergency that warrants this, particularly when nobody will be home. If you need to leave, shut it down.
The mere fact that he has to ask the question says that it is a poor choice.
Why not?
Trust me it is done all the time. When we fill silo the blower tractor is at WOT for hours. Yes there is someone "around" but it isn't exactly attended. I worked for a pumping company for a while a few years ago and we would take a tractor out to mid line and let it run powering a pump for up to a day at a time.
The mere fact that he has to ask the question says that it is a poor choice.
This site would be pretty dull if you applied that reasoning to every question asked.