Seeing this quote from Alex Russell (of dojo fame) almost makes me want to adopt Dojo into MindTouch (although it's too late for that decision...)

JavaScript cannot save you. Even if it could, you should not let it, for the price of this short-term salvation is the end of what you like about the web.

I have long been a huge roadblock inside MindTouch for pushing too much logic into JS due to the sentiments above. In my experience, Javascript has best been used to connect different pieces - if you try to make it do more, you will run into a lot of headaches (not to say it's not possible, but are you SURE it's the best way?)

Read his whole list of orthodox heresies.