What does 'execution dependent' mean?
Development executives will sometimes, nay regularly, hear pitches where the premise and/or story might sound OK but the idea won't entirely convince that it's something people will want to see. In this regard, they say that the idea is 'execution dependent', as it relies entirely on how well the screenwriter can spin the story.
If the pitch is coming from a new, unknown writer, then a mention of 'execution dependent' means a polite rejection. If it's from a more reliable scribe, then the exec will feel more confident in handing over some development dosh.
John August on Execution Dependent