Case Study #1
I don't think 'My Sweet Lord" by George Harrison was similar enough to to Ronald mack's "He's so Fine" to be infringing copyright.
Case Study #2:
Did the 1995 movie 12 Monkeys starring Bruce Willis copy artist Lebbeus Woods' pencil drawing done in of 1987 of his vision of a chair?
Yes I think they are very similar and Woods did very well out of the court case in receiving a 6 figure cash payout from Universal Studios in return for allowing the distribution of the movie to continue. Good on him.
Case Study #3:
There are definately original images and music tracks that are identifiable on the clip. I think this work is very cheeky and yes illegal but because it has been adapted and layered so much maybe not?! All artists get influenced by other artists work. If I had to be the judge I would find Keir Smith guilty of copyright infringement. Clever way to oppose the copyright laws.