That's just not the case.
Low lvl GLD tutorial:
On a boss:
Lead with shield lob
Repeat hate combo
FoF on cooldown
^ if you can't hold with this, update your gear.
If you're on trash and the DPS have split targets:
Flash -> Flash is about 40% better than fast blade -> savage blade. If you can hold a boss, you can hold trash. If you can't hold a boss, see boss tutorial above.