As an answer, AoxomoxoA sent me a video a few times. Which I didn't notice of course, since I was busy with other things ;)
The answer is: you don't see things you are not looking for. In the video above, you are asked to focus on the amount of passes of the white team. Hence you miss the moondancing bear.
What's the remedy? There seem to be two directions of thought here.
If I want to see the bear, I have to focus out, and forget about the instruction "count the passes". The problem with that, is that there are a zillion things to see. The details of the clothes, the gender of the participants, if they are wearing glasses, how the bridge is build, the colour of the ball etcetera. And every time I can ask you a question about the video about something you probably didn't notice. Most of the information isn't relevant, and is just a burden for the STM when noticed. If you are delivering a forced mate, the information that your rook is hanging is redundant.
In stead of focussing out, you can guide your focus by means of a thought process. The problem with this is, that a thought process is truly slow by its very nature. The conscious thought process in itself is a tremendous ballast for the STM. The hope is, that somehow the unconscious mind will work its magic some day, and that the thought process will become internalized and taken over by the unconscious mind. The unconscious mind of an adult can be taught how to drive a car in about 50 hours. I have dabbled around with conscious thought processes for hundreds of hours, but I never had the slightest indication that this will work.
Which way to go?
Both directions don't seem very promising. As said in a previous post, you need stronger cues. Not only before you start to calculate you need the information to pop up, but even during calculation the necessary additional information should pop up. If it takes an average of 50 seconds for a cue to fire, you won't come very far. Which in fact happens to be the harsh reality.
So I will try to find a third direction. From the 22 errors I analysed, there were already 3 missed knight forks, 3 simple takes, 3 overworked pieces and 2 mates. So the list of oversights might be not very long. Around 50 at most, I guess. I'm going to dive deeper in this list of oversights, in de hope that I find a way to tell my unconscious mind to not longer overlook these trivial facts.