Why does Simplepie return feed items in a wrong order?

I have this feed from picasa (correct but arbitrary, desired order).

The result is messed up

It's fine in regular, sorted by date feeds, but not these. In the object I get from Simplepie it has a messed up order. I don't do anything fancy just loop over the results and display them in the found order using my commercial gallery plugin.

$rss_items = $rss->get_items(0, $rss->get_item_quantity($limit));

I have tried this (hooked into wp_feed_options) but it doesn't change anything: $rss->enable_order_by_date(false);

Also, when I do var_dump($rss_items); I get an array that is represented by 546503 lines of text. I don't believe that's normal, maybe it also hogs the memory, but I can't even look through that data manually to see if the order is inherently bad or just gets mixed up somewhere.

Also I can't tell if it's Simplepie's or WordPress' wrapper's fault.