Doing some testing with for @tyzoid on IRC, I did some poking around- I tried putting a different command in that mount file, and to the best of my ability I can't find it getting executed. Also, I'm not sure how Nautilus handles MTP, but if it's through gvfs, then something strange is happening- it works perfectly even though AutoMount is set to false in /usr/share/gvfs/mounts/mtp.mount, just as was mentioned. Trash, however, is set to automount.- proving that it does make a difference. I feel like this isn't the right file to be editing. (No idea what is, but oh well..). Does this AutoMount just mean when the system starts, and not when plugged in as @kyrios123 implied?