>You did read the hyperthetical part?
Yes I did but I completely disagree that John and Dave songs would have made little difference to the success of DS.
Both Pick and Dave have said that they were much happier playing pubs and small venues so were happy with the Hope and Anchor while both Mark and John wanted,perhaps needed,Wembley Stadium and the enormous shows-Ed certainly did 
Most of the band were great at being backing guys for Mark but couldn't cut it on their own.There is nothing wrong with that and they were part of something magical which is better than most can say.
Exactly, being a musician is not that bad at all. Cliff Richard is a great frontman, but in his backing band, only Hank Marvin could play guitar like THAT!
My thinking is that they all [Dire Straits] wanted to be successful and be famous (who wouldn't?). Though Mark always says fame is a bad thing, however, I think John in his book clearly stated that they really wanted it. If you don't want it, you may never achieve it. They also never knew what will be the level of this success and fame, nobody knows. And it turned out to be so huge that it tore down the whole group, and made MK into the legend and guitar hero we all know and love.
Imagine Mark would be less of a songwriter or a guitar player than we know. Imagine his songwriting and playing would be on the level of his singing. He would struggle to fill the albums, they would need to resort to adding songs from David, John, and whoever else. Mark would have no choice but to agree to the democratic state in the band. And chances are this band would be an obscure band that few people know and follow.