Animal Frat - October 19, 1967 - S2-E12
Factual error: When Sam is in the library, there are multiple book titles visible that were published after the show's date of 1967. The clearest is when Sam and Duck tussle, the book "Men How To Understand Your Symptoms" falls on Sam - this book was first published in 1986. (00:29:00)
Animal Frat - October 19, 1967 - S2-E12
Revealing mistake: When Sam and Al are walking and talking, just after Scooter (being chased by the dog) throws Sam the dean's prized basketball, Al's shadow is visible on the ground, though as a hologram he doesn't actually have one.
Animal Frat - October 19, 1967 - S2-E12
Audio problem: A dog runs by Sam chasing one of the frat pledges. It's barking according to the audio, however the dog does not bark.
Answer: Sam threw items off the raft to lighten the load, so it wouldn't sink, in doing so he made the raft less heavy. Which made easier to float with the currents, if it was heavy the raft would have moved slower and not moved so far.
Except that Al said that immediately after throwing stuff out of the boat four hours passed and it was shown that they didn't really move from where they were. They were still in the same spot. Forgot to ask this too. When Sam and Vanessa are stranded on the island, one of them, can't remember who, did something and when Al appears, he tells them that because of it, time had suddenly skipped several more hours and if the event hadn't been interrupted, they would have been rescued by a boat. So, what happened on the island that once again caused time to speed up? It seems kind of strange that time could move so quickly on the island, especially since it was still day time and it never showed any sort of changes like the sun or clouds moving.