No, it isn't. Working alone is how one concentrates and, if lucky, attains a Flow state. Please read ,my article and please take it seriously, this is the straight dope.

A methodology is a structured set of practices, not a catch-all for how someone wants to work. The ones people are using now are concentration-killers, but instead of returning to what worked before they just pile on more distractions, like making development secondary to testing.