Hence why I said "While it is likely true for the specific props".LadyTevar wrote:I will point out that all the pictures you present show the flange running back to front, which follows the ridge of the helm and actually strengthens it as well as adds to the deflection of any downward blow. Lannister's flange goes from ear to ear, bisecting the helm's ridge. While it may stop a downward blow from hitting full-strength, the energy of the blow is concentrated on a smaller area, where the flange meets the helm. Depending on the welds holding it, that sideways flange could either come off, or be driven into the helm itself. Either way, that flange seems build for looks only.
But again, there is lots of historical precedent for sideways as well. While historically they are mostly placed at the forehead facing forward.
So if those had been built for combat then I think that they'd not be a detriment at all, quite the opposite. Such features easily add to the deflecting capabilities while adding only little weight. But had it been me I'd go for forward or upwards facing rather than the slightly backwards facing of the ground troops, or the very much backwards slant of -tywin's headgear.
Also note that in a fight most blows wouldn't come from straight forward vs the top of your head, so a sideways ridge would protect more then a back to front one. But the front to back one is so much easier to make for the smith as well as looking great...
Note that as Thanas points out that during the development of roman headgear, they start adding such stuff more and more as they face different opponents and thus weapons. The forehead ridge is quite typical of the most advanced roman headgear.
http://en.wikipedia.org/wiki/Imperial_I ... ial_Italic
You'd also see such sideways stuff added as a sort of cross in siege helmets, probably to protect from stones.