I have not solved one in 5 seconds but it is not difficult to learn how to do it. You just need to want it. I took really slowly to learn but I have now done multiple times. I never checked the time I need but I suppose with the classical system, it is about 3 or 4 minutes. If I am not distracted I suppose 3 minute. I used the method of step by step to learn it. You learn a move, then another, then another until you know all the steps and you need just to practice.
Anyway, great job for this guy to be able to do in 5 seconds!