Let's go through my list:
- I don't think many people would enjoy FFH as the ADTOE song (not that it was really a monster song anyway)
- Outcry could've only been represented in 2 tours, but was only represented in 1 of them, so it hasn't really had a good share of plays based on how many tour cycles it's had
- Breaking All Illusions wouldn't be nearly surprising enough to be mentioned so intentionally vaguely by bosk as "the ADTOE song"
- Illumination Theory is unlikely, since it has only been in 1 of 1 possible tour cycles
- Same applies to AFTR, & it isn't a monster track either
- Caught In A Web & The Spirit Carries On could apply to the "surprising number of plays for how many tour cycles it's had" (especially the latter), but they're by no means epic monster tracks.
- Scarred & TDOE haven't really been represented in DT's setlists that much, only recently has they gotten that many live plays
- The Great Debate isn't a crowd-pleaser, & from what I could find, there aren't any versions of SDOIT that include the title song as one track
- Finally Free would be my answer at this point, but the era between 2009-2013 where it was hardly played at all is giving me the opposite impression, in fact, there's only been five years where the song was played that often: 2000, 2004, 2007, 2008 & 2014.
tl;dr I'm confused