An unresolved thread in the momentum of the central naritive of a motion picture forcing an unnecessary leap of logic on the part of the viewing public to explain, often contrary to or conflicting with previously defined elements and character behaviors established within the movie or movie franchise. Would you like to know more?
The role of Cade was probably written as Sam during early planning. (my guess is that all of Sam's exposure to the Cube, Matrix, and the Primes themselves might have turned him into something of a mad scientist inventor.) There were definitely spots of dialogue that sounded exactly like something Sam would have said, really. The space ship insurance scene was 100% a Sam scene. At any rate, Cade being an inventor in the middle of nowhere seemed kind of out in left field to me. Once Optimus was there I didn't even think about it again during the film though. Rusty G1 Optimus was cool as hell.
This is probably the only legitimate complaint about the movie I have. I've mentioned this in other threads, but I would've *loved* a scene where they're sitting down and Optimus is explaining why they had to break off contact with Sam, Lennox, Epps, Simmons, etc. and seeing Bumblebee looking sad about it. Just something little like that would've been better than the nothing at all that we got.
My personal headcanon is that Sam was murdered by Cemetery Wind, which is why Optimus wakes up roaring "I'LL KILL THEM! I'LL KILL THEM ALL!" Because the people he thought were his allies killed his closest friend in cold blood. Just my take. EDIT: NEST deserved more too. Again, you spent 3 movies establishing these returning characters again and again and then you just sweep them under the rug and ask your audience to pretend they don't exist. Yeah I don't think so. And regardless of whether Shia was an annoying actor or not it's called "continuity". Tyran was quite consistent when it wanted to be right up until AoE.
I don't feel like they swept anything under the rug. Ratchet explains it right off the bat that OP has ordered all of them to sever ties with humans. That's the only explanation I needed for the old human cast
"Continuity" has never been a high priority for the Transformer films. The first three films didn't make much sense, so why should the 4th?
I was surprised by how many people I know that think it would have been better with Sam back... Sam's character was whiny and annoying, went from 'I wanna be a normal teenager to I wanna be somebody with the Autobots I saved the world!' I'm glad this film focused on Optimus' relationship with the humans rather than BumbleBee because BumbleBee doesn't talk and that means Sam gets more lines when around him...which sucks...XD I'm also thrilled Tessa got more to do in this film then the last two girls whose only reasons for being there was 'oh my boyfriend is friends with he Autbots' Tessa was a bratty teenager but she held her own on Lockdown's ship and did chose to stay with he Autobots over turning themselves in. Again I liked Carly taking a stand against Megatron but...that was it. Better hearing Cade offer to help Prime then Sam spewing 'OPTIMUUUUS!' every time he's in trouble.
