Interesting article except from your test percentage claims, they feel a little hand-wavey
Kalispera! I would agree with you that when you have a lot to do, these numbers may seem unrealistic. It's a common thing and there is no issue with it. There are two things to keep in mind though:
a) 100% code coverage is an asymptote and a number to keep you a bit mindful on your tests. You can never reach that number, but you can be somewhere close to it. For example, recent project I was working on had 83.7% and we were happy with it.
b) Even if you think that you are too busy to write your tests, you have to remember the most basic law in TDD, which is that you have to write the minimum amount of code to make the test pass. That's why TDD reduces bug density and development effort.
Also remember that TDD and testing in general is a discipline and you get better and better with it over time. Happy coding my friend!