Of course you'll lose that fight. I don't go in Wards. Smart players avoid them like the plague. Destiny isn't full of smart players though... And Barrier melee lasts between 10 and 20 seconds depending on perks and if you rock NBP. Razors Edge is extremely small and easy to strafe or full hop over, unless there's a low ceiling or you're in a tunnel, which is arcblader territory.