Actually I cannot duplicate how I had a 5 or 6 minute buff , which happened one time.
Currently you always have a 60 second buff no matter how many skill points you put into Able Navigator and higher, which currently is not worth the skill points imo.
I would personally change the base to say 5 minutes, or keep it at one minute but each skill up adds a lot more percentage.
Either way I think it needs to be fixed