Here's what I do..
1) After downloading the video, I make some changes to the audio such as changing pitch, tempo, speed etc.
2) I also change the length of the video by adding a slide at the beginning and the end of the video. Usually it is Download this song's ringtone at ... and so on. I would also change the brightness and add effects to video itself.
3) I will also change the file type from mp4 to say wmv. I check for the file properties and remove all traces of song name, artist etc.
4) While uploading, I upload the video with random title, without any description and tags and upload it as private video.
5) Then I let the video sit there for 2-3 days and I view it 25 times (max permissible views for a private video).
6) After 2-3 days I add title, description, tags etc. I also add the words "no copyright claimed or intended" and then make it public.
So far none of my videos has been deleted.
Hope that helps,