I inserted some JS code via the console that scrolls to the bottom of the page whenever the 'collection-assets' div changed, waited, ran observer.disconnect() as my browser was crashing to a halt, and then saved the HTML and combed through it with regexes.
var target = document.querySelector('.collection-assets');
var observer = new MutationObserver(function() {
window.scrollTo(0,document.body.scrollHeight);
});
var config = { childList: true };
observer.observe(target, config);
Right, I tried that first but I couldn't actually get it to return any data. I think I was screwing up the request headers. Now though I remembered the Firebug "copy as cURL" thing and it's working, so yeah, definitely a better way to do it.