Excellent! You article completely explain what I feels about BEM. Where I work, we adopted BEM and its awesome. One of the negative points that I can say, is for how use BEM with SASS or any other css pre-processors. We created/mixed an mixin to help the BEM block and modifiers creation, but it seems to confuse the SCSS map generation. But, its a fact that the benefits override the negative points.
I suppose that your team use any pre-processor right? Have you created any mixin to generate the BEM blocks and modifiers? Did you have any issues with this?
Ps: Sorry for my poor english.