Some of you may already know why... but not all of you ...
So let's explain it the simple way...
When you download something your application don't simply download it by itself using some dark magic ....
When you download a file your application has to ask other application if they can send you a part of it...
By doing this you need to use your upload bandwidth to ask him to send you and use your download bandwidth... so if it takes 3minutes to ask to download, you'll download 3 minutes later ....
That's why it's BAD to limit upload speed with a third party application
That's why you need no upload
