Plot hole: Daniel first needs Miyagi's signature (which Miyagi refuses) to enter the tournament. However the rest of the movie focuses on Daniel's signature needed to enter instead. Didn't Miyagi officially need to sign? How did it suddenly switch?
Suggested correction: Daniel's entrance into the tournament was engineered by Silver. Mike got Daniel to sign, then had Silver or Kreese sign as the sensei. Silver started training Daniel shortly after, so he is the most likely one to have gotten him in. When the plot was exposed, Miyagi and Daniel probably contacted the tournament officials and corrected it. They wouldn't have told them about the plot since they knew it would have meant more trouble with Silver, Kreese and Barnes, so it's plausible that Daniel could have gotten into the tournament without Miyagi's signature.
