Most of what gets written about pitch trailers is written to sell you one. This is the other thing. Everything here is what I would tell you on a call, with the sources so you can check me.
The $23,000 Whiplash short unlocked a $3.3 million feature that grossed fifty million and won three Oscars. Saw was greenlit off one scene. The verified ledger of proofs of concept, what the industry itself pays for one, and the numbers to know before you accept anyone's quote. Including mine.
Frontières at Cannes runs a section literally named Proof of Concept: two to five minutes of original footage, or you are not in. The Gotham's Shorts to Features track goes further, the short is the application. The requirements, verbatim, and what they actually mean.
The single biggest thing that decides whether your sizzle is good is not who cuts it. It is what you hand them. Most people hand over the wrong material, hold back the right material, and do not know the difference. This is free and it works whoever you hire.
More as I work it out. If there is something you want explained properly, tell me and I will write it.