Part 5 of the series "Ableton Live Insider Tips" explains what the command NoAutoArming does, that you can add to the Options.txt file and what it might be useful for.
Download the Options.txt file with the commands from all the video tutorials (Right-click and choose Save Link as) Don't forget to only keep either -NoAutoArming or -EnableArmOnSelection as they conflict with each other.
Questions or suggestions? Leave me a comment below. :)
You can find the initial instructions in the tutorial Options.txt Part 1. Onwards to Ableton Live Insider Tips - Options.txt Part 6.