This also affects anyone using latex2edx (
https://github.com/mitocw/latex2edx) or moodle2edx (
https://github.com/mitocw/moodle2edx), both of which generate course
content XML directly, instead of via studio.  Studio is currently very
handicapping for any course authors wanting to use non-basic features, such
as AB testing, randomization, conditionals, custom XModules, or custom
XBlocks, just to give a few examples.  Beyond the large number of MITx
course authors at MIT working this way, I understand there are other
Xconsortium users who either have already been using latex2edx, or are
planning to do so.