This move is terrible in comparison to the Guardian's "Guardian Leap", I'd be so bold as to say it's just worthless as is and the fact that it's a combat proficiency skill just makes it all the more insulting to the Vanguard tank.

A Combat Utility that reduces it's cool down, gets rid of activation time and adds some kind of damage buff to the player would put it on par with Guardian Leap.

Personally I would replace Guard Cannon with a new Utility that benefits Transpose, as Guard Cannon is damn near useless as well.