What exactly is the point of Vow of Strength? It disables your attack skills for 10 seconds, and during that time your attacks deal a whopping 21% more damage (assuming you have 16 earth prayers...)? And this is an elite skill? Assuming you hit for maximum damage with every attack, that would be like 8 more damage per attack...
What could the point of this skill be, and who would be dumb enough to use it in its current form?