Poor choice of examples. The whole antennagate was not a design issue at all. It's as an natural issue that was shown to effect dozens of non Apple phones and was only an issue for some .01% of iPhone owners almost all of whom readily admitted that they live in areas with crap cell phone service in general. Even the Consumer Reports review noted that this issue was only an issue if your service coverage was crap.
And who is to say that this guy wasn't overusing his iMac compared to standard usage models and burned out the properly designed and installed display himself. He does say he was using it as a home media center. That means potentially having it in for a good 2 hours or more at a time, likely with full brightness etc. And if he was using it in his music classes that could mean even more use every day. Could go as high as 8 hours in a near solid stretch. Few of us use our computers that much every day so we wouldn't burn out the display so fast. But he might. Which means it's not a defect at all. Whether anyone in those 320 pages had one or not.
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Says the doctor who has never treated nor met the man. And yet magically knows exactly what is wrong with him and the best treatment.
There is no magic involved at all. Only experience of fixing this particular issue and rather simple logic.
The 27" iMac LCD panel has two LED trays. They are both along the bottom of the panel and meet in the middle. The power is supplied via a cable that enters the very bottom corners and is soldered onto the the LED tray. This gentleman has been told that he need a new LCD panel. Logic dictates that the backlight board has been excluded as the cause. Therefore, the only possible conclusion is that the actual issue is the one I have referred to.