Is everything else between these two groups completely equal? I seriously doubt it is, in which case I don't think it's fair to make any conclusions that hold weight.
This is one of the problems I have with these sorts of things. My company went Agile about two years ago, and lots of people like to rant about how much better everything is now and how much more productive we all are because of it. Except we actually have no way of knowing whether it made any difference at all.
Sorry, I should have made it clearer. I ranted likea personal thought than a definitive statement.
The teams work on different projects. The diversity and experience of its members are different. They are not strictly comparable.
But, looking at both teams from above, it feels like the non agile team is very simple and it works. The agile team is more complicated and works only on paper.
From my personal experience: experienced teams can thrive with almost no methodology and an ad-hoc process because... They had experience with other processes and can see the good and bad in them.
I still advocate agile for less homogeneous teams or in situations like other posts have highlighted but a team of more senior developers with a working process that is open to be improved (one of the cornerstones of agile) will thrive with less churn than when forced into a by-the-book agile process.
For me Agile is by definition an ad-hoc process just one with guiding principles for how to go about organising it. The problem comes with formalised methodologies based on Agile which are treated as a one size fits all approach for any team.
This is one of the problems I have with these sorts of things. My company went Agile about two years ago, and lots of people like to rant about how much better everything is now and how much more productive we all are because of it. Except we actually have no way of knowing whether it made any difference at all.