This system might work with many people but not with all. Some people just don't have patience to do this kind of practice.
And they may never succeed because of that. If the concert tempo is 100 or more, it is possible to start practicing even slower - at 40 or even 30, I think.
Actually the best way to go about the practice tempo is this: pick such a tempo in which you can avoid making mistakes. Simply resist the temptation to go to the next note unless you are absolutely certain that it will be correct.
The real trick is NOT to play all the voices or parts at the beginning. Then your progress will be much faster and you will feel much better about practice. Very gradualy you may speed up the tempo but only after you can play at the current speed correctly at least 3 times in a row.
By the way, do you want to learn my special powerful techniques which help me to master any piece of organ music up to 10 times faster? If so, download my video Organ Practice Guide.