Not really.
He calls it a vertical slide. Meaning it was something playable, but simply not finished.
E.g. instead of having a general AI that will have a car chase you down, they'll script up a scene in which a specific car will chase you - which is exactly (and saddly) what is in the game itself.
It also means people are writing code and designing levels (wallclimbing + specific walls to use that on), which are thrown away afterwards, as they need to implement it in the right way (if at all).
And seeing how similar what was shown is to the actual game map and sotryline - it's very likely a copy, paste + patching holes from the actual development at the time.