You said: "While on the job, women either do as much work as men or are simply too unproductive to be viable employees." and you are ignoring the 3rd option, they are less productive than men and receiving less money for it. That's Block's whole argument.
Are you an economist yourself? In that case, which school of economics is your preferred one?
I did not ignore his argument. I explained why he was simply wrong. You even quoted the section where I explained why he was wrong. There is literally no incentive for an employer to continue paying someone (even if it is less money) for lesser work. His third option is a fiction and you've taken my dismissal of it as simply "ignoring it". When an employer hires someone, they factor in the most they are willing to pay someone for the desired work into their budget. They don't reign it in if the work is shoddy since they get nothing out of it. It would be better in the long run to simply hire someone else who won't do shoddy work. They would save more money that way. Not a single employer will look at an under-performing employee and say "we will keep him on, but pay him less". Nor do they hire someone on the expectation that they will "work less, but at least we can pay them less". The gap comes about well after someone has been hired, and it can simply not come about due to poor performance. Poor performers get fired. Block didn't even bother to prove his point. He just threw together a blatantly illogical explanation that fits with his Darwinian, free-market bullshit. I can see how, if you believe in the free market, you might be tempted to apply it to microeconomics in the way he has. Unfortunately, that nonsense is only passable in macroeconomics, and even there people have caught on.
It should be fairly obvious where I land as far as schools of economics are concerned.