I will try this again, hopefully without rudely stepping on the toes of the "experts" in here.
Freshwater dips will not cure ich as someone mentioned before.
Freshwater dips will kill the ich parasite which the host fish has encapsulated just under the skin. As the parasite can't survive in freshwater.
As for a speedy cure all, there is no such monster available for the treatment of ich. There are as many treatment preferences for ich as their are posters on this site. Each has its benefits. One has to develope a program which will work the best for him.
Ich is a parasite which capitalizes on the lowered immune systems of the fish. Many things will cause a fish to have lower immune systems, more notably is stress. As with most things in the aquarium hobby, prevention is the best route to take.