it probably slows things down , either that or u are too exciting for ur download to get finished that u arent exactly eager to do something else . 1)you are hysterically waiting till its finished and 2) everything done in the meanwhile seems like a waste of time because when the download is finished what u were doing will be stopped immediately thus it seem futile to keep urself busy meanwhile
Like in this scenario : say u are going to the movies in half an hour, now 30 minutes are a lot and u can provide urself with many things in the meanwhile , tho most likely u will be bored during those 30 minutes waiting till u go to the movies.
Why? because ur mind is too distracted so its hard to keep urself busy , just like with the download.
If it slows things down you can do some little (pretty simple) tricks to counter that.
As for the excitement...well I didn't consider that. I have never been excited for a download (because House M.D. episodes were very fast to download xd)
Well this download is 11gb and my connection is really slow .. So I can't be on the internet because it will download at like 100kbps than and I finished Dragon Age Origins and now I don't know what to do while this download finishes ..