The Boss can, without question, stand alone and deliver the goods. There's a reason why it's just his name on all the records.
But in my mind, it's Springsteen + The E Street Band that truly provides the oomph.
As a total aside, this also reminded me that the Silver Bullet Band was always printed right with Seger's name on their album covers. Different band, different dynamics, but there is a reason why he's known as The Boss.
I am sure that caused it's fair share of acrimony between band members -- though to everyone's credit Springsteen, Little Steven, the late great Big Man, Mighty Max, Lofgren, Tallent, Bittan, Federici, and the rest never seemed to have a problem getting back together.
But I don't recall Seger and the Silver Bullet Band ever seeming to have drama.