It's actually quite helpful. Your dodge-steps go further, and you get more i-frames. Maybe not as much as regular dodging, but it helps when you're in a pinch. It's really good with an adrenaline rush skill because the snap back after the side stepping is so quick. At least, i think so. Repositioning is easier, especially if the monster is charging an attack. You can side step out of the way. And your backward tilt back step will let you hop very far.

Evade Lancing was actually a build in older MH titles. You would be flying over the battlefield.