Yes, very true. I wonder if this function is just never actually used. I tried the [demo](http://build.fluidproject.org/infusion/demos/uploader/html/uploader.html) with a large file. The behaviour of the uploader seemed correct and I didn't get any errors in the console. However, I have filed a but about the lack of unit test for this function. 

http://build.fluidproject.org/infusion/demos/uploader/html/uploader.html 

Feel free to fill it out in more detail as needed.