Board Thread:Misc./@comment-27255656-20170508190720/@comment-25322628-20170818013524

Most likely, it has to do with the fact that Titans have a tricky mass. A severed arm was confirmed to be weightless.

It may be due to a subconscious requirement for weight whenever they do something if they're mindless.

The Armored Titan makes me suspect that it only needs weight when hitting something, like a gate, providing more force.

Hopefully, the answer will be revealed in the future.