Other mistake: When Eddie Valiant gets thrown out of the Ink and Paint Club, he is already starting to go through the air as the gorilla moves his hands to throw him. (00:21:20)
Other mistake: At the beginning of the movie, when Roger is begging the director to give him another chance and keeps grabbing the bottom of the director's jacket that is in the director's hand, at one point the bottom of the jacket leaps into Roger's hand before he actually grabs it. (00:05:05)
Other mistake: Three shots after Eddie stuffs the soap into Smart Guy's mouth, when the other four weasels notice him tumbling down the stairs, a chair can be seen flying across the room. This is impossible, because the other four weasels are together, and Smart Guy was talking with Eddie, so there was nobody to throw the chair. (00:42:15)
Answer: Valiant also shares his name with Arthurian comic strip hero Prince Valiant, who wields a singing sword, Flamberge.