I don't understand that article at all. I see no weird dynamics. The company owns the work they pay me for, nothing else. In the games example they either paid for the game ideas or they did not. If the worker provided them that's basically admitting to it being done as part of work. Trying to protect against this small ambiguity by owning all my work is the wrong way to go about it.
That was my initial reaction. If the employer's sole concern is to avoid using IP they don't have full rights to, then they can just require me sign over rights to my IP which I used in work projects.
That approach does create more complications though. What if the employee claims that they weren't paid for the game idea and didn't present it to the company, rather that a coworker learned about it off hours and "stole" it[1]. Or if an employee writes some software entirely during off-hours, but incorporates the company's trade secrets or patent pending ideas into that software. To avoid this, the company now has to document that rights for each work was transferred from employee to employer, and it has to document what is and isn't considered a trade secret, so the employee knows what information they learned at work they are and aren't allowed to use in side projects. From the employer's perspective it is much easier and safer to make the default that all IP rights are assigned to employer, and then document any exceptions they might grant.
In other words ideas (patents, trade secrets) are much messier than works (copyright, physical objects) when it comes to employee / employer contract.
[1] Also "game idea" was a poor example because game concepts/rules are not covered by patents or copyright, just trade secrets prior to publishing, but I'll continue his example as if they were.
