The headlight relay mod is just a band aid, used to side step and hide faulty wiring harness connectors and switches. It only solves a small portion of the real problem
Well I disagree a bit with that, though I know you know far more than I do regarding m/c electrical systems ...
From what I understand it also lightens the load on your expensive and hard to find (for some models) switches. Also,running heavier gauge wire for the power to your headlights and or horn and relays allows you to pull more voltage for higher powered aftermarket items safely. Sure it is not a replacement for having a properly functioning wiring harness, but it helps in this instance even if you do.
