Hello jamesray
It depends on how long it takes for the trader to fully understand this business, also what way the trader sees this business (pleasure or serious).
Once I found, what I believed to be the right strategy from "Demo" trading, I started "Real" trading, this took well over 6 months and I only trade for fun.
Others might find their ideal strategy in lesser time, while others might never find it.
One good thing about this business, you'll never stop learning, and most likely always need to fall back to the "Demo" from time to time, even if its only to double check on your strategy.
Good luck
Liz