I don't think proof of intent would change a verdict, but it certainly could have an effect on the judgement for damages. I agree that establishing a universal line is impossible, but I think it can be done on a case-by-case basis. Legal precedents that push copyright protection beyond melody and words, in my opinion, are a necessary evil needed to protect songwriters and publishers. The downside is that such precedents could result in mountains of future lawsuits tying up the court system as millionaire artists frivolously sue other millionaire artists, each trying to move that line in their favor. I would love to be a fly on the wall in the courtroom to hear both sides. They're no doubt going to bring up all the points you made. In case Ed's defense could use a little ammo, I would urge them to look at the music I play... Slovenian-style polka music. Even though there are many hundreds of polkas in existence being performed and recorded by artists like me, almost every song shares the same beat, tempo, and instrumentation. Many share the same chord progressions and song structure. Their only differences are in the melodies, and even then, some songs have melodies that are so strikingly similar to other songs that any juror pulled off the street would declare them to be the same song. But in polka music, this is the norm. Unlike Slovenian-style polkas which conform to accepted similarities, Sheeran's and Gaye's songs are both soulful pop ballads. Such ballads should be allowed to share similar-sounding elements, whether they are chord progressions, instrumentation, tempo, syncopation, etc. but in my opinion, since soulful ballads are not a specific subgenre of music, they shouldn't share so many of these elements simultaneously that they literally sound like the same song. Regarding greed, I think it's possible that the owners of "Let's Get it On" might be in it for the money. Just about every lawsuit of this nature is a money-grab in my opinion. But I do believe legal recourse is warranted in this particular case.