[danbruc]

What then is a more fair outcome in your original scenario where producing widgets was the only activity?

If you keep working, making other inventions, that is a completely different scenario. That you should do your share of crank turning only applies to the scenario where turning the crank is the only work that needs to be done.

[jedberg]

Clearly crank turning isn't the only job, since machine inventing must exist as another possible job.

But even if the machine is the only invention that will ever be made, it's still not fair that we each crank the handle the same amount of time, because I invented the machine. I built the machine and presumably spent my widget money on making the machine. My contribution was amassing the capital and resources to make the machine. I should get some benefit from that.

[danbruc]

I already wrote that you can have some additional widgets for inventing and building the machine. Even if I had not mentioned it, that would be a reasonable thing to do, if I insist on splitting the crank turning work, you can pretty safely assume that I am also willing to split the inventing and building work in one way or another.

But even if you would not get anything for inventing the machine, it would not really matter significantly. As you both keep turning the crank, the relative amount of work you both did would approach one half and both of you would have half of all the widgets. Compare that to the other scenario where the guy does all the crank turning, there the relative amount of work you did approaches zero as the guy keeps turning the crank making his relative amount of work approach one.