Well, maybe. But I quoted Luke Skywalker, so...
But here's my more detailed response to your points:
1. I wouldn't put it anywhere near the top of DT's catalog. But that said, it's still a great song.
2. The lyrics are good. But that's about it. And they aren't really JP's. At least, they aren't a "JP original." He took the works of the manga that the story came from, and just retooled them so they worked for the song.
3. SC and BCSL are the only DT albums that I don't generally listen to in full and have "re-cut" them. As part of my abbreviated SC, I start it off with ITPOE as a whole song rather than in two parts bookending the album. So I do agree that the best listening experience is the entire thing as one piece. But that said, I would hardly call splitting it a "mistake." I fully get why that creative choice was made, and I think it works just fine in context of the album--especially on the heels of the previous three albums that ended with a mega-epic (Six Degrees), an epic (TOT), and a mega-epic (Octavarium). They just really felt like they needed to do something other than having a 20+ minute song be the closer. At the time, it felt right. And it made for an interesting and different listening experience.