Hi Bernard, 

If you're facing a group of technologists who just want to 'get things done,' in addition to educating them about the typical place for BA's I would also start looking for was to add value to them directly, regardless of whether it fits into a 'typical' BA definition.  Think of them as your business customers: what can you do to improve their life?  Since this group is working hard/overworked, what things are the grumbling about that's causing them pain?  What things are they dropping that they would like to do but don't have time to do?  

Come up with ways to support their work processes and improve their efficiency (using requirements analysis, solution assessment, etc.) and then you'll have a real-life example to demonstrate your team's value to them.  Even if it's something small but has great value to them then they'll realize the benefit of including you in their work processes. This combined with an education of how you're accomplishing these gains for them and they will want to leverage you as much as possible.