Epic is such a relative word to use... I usually quite like DT's longer songs, but the album is pretty long, so I don't think we're losing minutes here. And some of the songs might be pretty epic by themselves (Breaking All Illusions, Outcry, Bridges in the Sky).
Coming from a DT perspective, I think we forget a little bit how long the songs we listen to actually are. I mean, everyone agrees that Octavarium and ACOS are epics (partially because they are such great songs, but more importantly because they are also 20 something minutes long). If you check most other band's albums, they rarely have songs over 15 minutes, let alone so many over 10 (4 just on this album). And most bands don't have such long albums either (with the exception of the first couple of albums, every DT album has over 70 minutes of length (ToT actually has only 69... but SDoIT makes up for that with 96), while most bands I've been looking at lately get around 40, maybe 50...)