Is there a reason for the notches on the blades? In Attack on Titan, the blades used with the 3D Manuever Gear have notches in them similar to those found on craft knives:





Certain knives like the one above come with snap-off points so that when the blade dulls, it can be removed and replaced by a fresh and sharp piece. However, a utility like this seems redundant on the 3DMG blades as a shortened blade would be extremely ineffective at removing a Titan's neck, not to mention that the blades seem to be used and discarded as a whole piece.
Additionally, The wiki page on the blades themselves gives no mention of the notches.

So is there any reason for the notches to exist aside from looking cool?
The blades were very prone to breakage [picture needed]. The vertical maneuver gear has even a spare blade storage built-in [picture needed], and in at leat one occasion one soldier was left without blades [chapter ref needed] and a companion had to share blades with him.

The notches make sense since the blades break so often even a short and less effective blade had a chance of scoring a kill and you could take the most out of a blade before it becomes completely useless.

Also, the resources inside the walls are scarce. Making the most out of the metal available also made sense.



I have no access to CR manga ATM, and cannot search for manga images. Will add the references later today.