and this is a narrative that i don't think plays to ... not necessarily "their strengths" but to what makes them truly unique. yes, they are good songwriters. yes, Bono and Edge have a connection. no, they are not Lennon/McCartney, nor should they be (even if they want to be).
the magic of U2 is creating a world within a song, and within said world Bono goes on one of his quests for truth, love, god, etc. think Bad, One, Streets, UTEOTW, even COBL. it's the full band effort that casts the spell and let's them do what no one else on their level can do -- the emotional transportation that happens when they are at their best. the Bono/Edge songwriting is a critical component of that, but it isn't the most important thing. they use their musical instruments as tools to world build, which was something i think they were criticized for (Edge only knows 2 chords! the music is too simple! Edge can't play fast!) and, as ever, are responding to.
it also seems as if they as a band are unable to work in a way that lets them build said worlds anymore. and that's life. the magic may well be gone, so the emphasis goes to what you actually can do with hard work: write well-constructed, highly-polished songs. and that's what the SOS project was about. "hey, underneath all that U2-ness, we are actually good songwriters, too." yes, sure. they are! i enjoyed some of SOS. but they are/were much more than that.
there was a passage in "Race of Angels" which I think is the most intellectually rich book written about U2. they were talking about writing "streets" and how Bono wanted to polish the lyrics more, but Edge stopped him, saying, "we don't want it to be smarter, we're going for something higher than smart." (remembering this off the top of my head).
now, it's about being smart. and i think we've lost something.