Basically it goes like this: Theres certain problems that seem solvable from your perspective, but the real problem is that the way in which the problem manifests itself deviates largely enough from one person to the next that it makes any solution non-portable to someone else's instance of the problem. As computer science techniques get better I would wager that this barrier gets thinner. I know that if I spent enough time on it I could solve this problem for myself. But solving it in a way that would help others too? That's a tall order.
There's a lot of problems that right now are near or on the deviation barrier. I like to think that as that barrier hypothetically thins that computers will be able to help us with more unique aspects of our lives and account for individual quirks.
But talking right here right now; I'm not sure that you would be able to find effective productivity coaches. Feel free to prove me wrong on this.