Tonga Tom

Does anyone know if it possible to give a command to start a new key frame? The use would be to be able to record an entire movie that has ads interspersed, and then afterwards edit out all the ads. Currently, either some portion of an ad must be left in or some portion of the movie must be taken out because a new edit must start on a key frame. If a command could be given to start a key frame right at the end of the ad, usually during a black frame, then the edit could be made to start exactly when the movie restarts. If this is not currently a feature, can this be put in a suggested feature that is available as a hotkey? Thanks!