By pressing C we should be able to look straight backwards.
For mouse users you can easily look all directions and hold your turret place pretty fast and easily with the right click and the speed of the mouse.
However for keyboard users like me thats not possible, I have to wait for my turret to turn completely to look backwards.
I think the turret should not start turning backwards unless while pressing C we press ? then the turret turns backwards directly, if you didn't know; for keyboard users the key ? turns the turret straight directly by just pressing ? once.
Or it could work differently but the end the point is to have the ability to look backwards straight away for keyboard users, mouse users actually can use this too since C is near AWSD.
Forum post http://en.forum.tankix.com/topic/2097-look-backwards-new-control-key/
Customer support service by UserEcho