if your are familiar with the system level files, you will know that in order to solve a problem like this involving "kernel_task", that you have to mess around with the system files. and since this person had already reinstalled the system, the worst he would have to do is ... reinstall the system... so he did the right thing, he did research, and then tried it. and his research turned out to be very good.
what he did was the correct thing to do, which was to remove a system level plist file that is regenerated by the system.
and most of all, solves the problem of "kernel_task" taking over the CPU processing cycles so nothing else can get done.
and if someone notices the "kernel_task" going haywire, I highly recommend doing this, and it will not harm your system, because it is just a plist file....
the problem one may run into is following those directions, one has to know how to open a package that you are at, with a right click, to go see the "content" folder... so they will have to have some knowledge to get to the file to delete it.
(oh and his battery problem, and high fan speed is/was some other problem)