Why would you put the artists name in the title? Just the song title is enough
Because until iOS 7/8, there was no "group by album artist" feature (and it still isn't on the iPods that don't use iOS) so if you have a song like Umbrella and have the artist as Rihanna feat. JAY Z then it wouldn't appear under "Rihanna" on your iPod even if she's the album artist.
Well, for the sake of my scrobbles, I don't tag any features on iTunes, but if I'm writing a list of songs, it's feat, like:
Lady Gaga (feat. R. Kelly) - Do What U Want
Meghan Trainor (feat. John Legend) - Like I'm Gonna Lose You
Demi Lovato (fear. Cher Lloyd) - Really Don't Care
etc.
Why would you put the artists name in the title? Just the song title is enough
For me, it differentiates between featured spots and full collaborations or duets. I put it in the title if it's a feature, but I do "Artist A & Artist B" if it's something like a duet with roughly equal contribution.