Aha - at last some interesting debate.
First off, I believe the buddy system is a cornerstone of diving, both during training and beyond - a kinda safety/social event.
As I dive more and more, particularly more challenging diving such as cold water/crap vis in the UK, I have learnt to both respect the buddy system AND self sufficiency/redundancy. Self-confidence in my own abilities is a state of mind. Example - I always (even 6m hops in the local dock) have my pony available, always carry a spare mask & knife. Why ?? - I have learnt from this and other forums of what has actually gone wrong and try to build in back up. You cant always rely on your buddy who has disappeared in the 2m vis so you have to rely on yourself. My pony is rigged for ME, yes my buddy can use it but if my life is threatened then the buck stops with me.
I will develop this further in the future by getting twins, dual bladders etc etc - BECAUSE IT HELPS MY STATE OF MIND AND HELPS ENJOY THE DIVE without the potential for anxiety ruining a dive. This may reflect on my state of mind - but hey, each to thier own. So yes, agree with self sufficiency
Given that I am/will become more self sufficient, will I try solo diving ?? - Yes I will. Bear in mind my idea of solo diving is not to jump into an unknown pit/sea and go for it - I would have to know the site well first which means I will start by buddying up a few times. Even then, I would not dive solo in a site where I was the only diver - I would dive solo in a site that I both knew well and had other divers present - again I guess its a state of mind.
So, to conclude - yes to buddy diving, yes to self sufficiency and yes to solo diving within the bounds of ones own ability and mind state.
Finally, when I am DM-ing on courses I am solo all the time whilst keeping a close eye on students who are being instructed - is this solo
??