All those working for large organizations must be familiar with how new ideas are presented at decision making management meetings. The proposal is expected to be well documented and thoroughly analyzed, ready to receive a go, conditional go (with minor modifications) or no go decision. The requirement for careful preparation is well justified at decision making meetings to keep the meetings efficient. However, sharing and open discussion of ideas should be encouraged at other occasions.
Every new person with whom the idea is discussed with will help to develop the idea way or another. The discussion may bring new ways for implementation to the table, it may reveal some incorrect expectations or it can point at aspects that need further clarification. – And going back to the decision making managers, to increase the probability of receiving a “go” decision to the idea, it’s not a bad idea to have an informal preparation discussion with the judges before the idea is officially presented to the board.
I encourage you to try this out starting with a trusted colleague and proceeding towards supposed antagonists to get the idea challenged early enough – sooner or later it will be challenged anyways and you will need to be prepared.