At the moment, it seems one of the biggest reasons why FA isn't getting outside help for the UI is because of trust issues, because it would involve seeing the code, which I'm assuming is because the UI and backend are intertwined. Would it not be relatively simple to export such code into external files, so that instead of the PHP for the UI having "select blah from blah and do some magic", it would just call something like GetLatestSubmissions(24)/GetUnreadJournals() and whatnot? Then once the UI is separated from the back end, anyone working on the UI only needs to know what these functions are, how they're called, and in what format the data is returned. An FA UI API, if you have an acronym fetish. At the same time, the back end can be fiddled about with endlessly just as long as the functions still accept and return the same data in the same way.
It sounds simple enough - just cutting and pasting and adding some intermediate variables, maybe massaging the data into a more suitable format for passing between functions - but if that were the case I'm sure it would've already been done. Am I gravely underestimating how difficult it would be? Is there something I'm overlooking or misunderstanding? Is the code just that awful? I wouldn't think it would be that bad, since even the user pages say it only uses 25 different queries, with about 10 of those probably being the ones for the top bar that are the same on every page.
Apologies if I abused any terminology. You get the idea though.