I don't have very much faith in the Rand report since it was produced under the self serving authorization of the NTSB itself. It makes an excellent case for increasing the size and budget of the NTSB. On the other side is the party system and its ability to bring product specific experts to the investigation. The balances at work in the party system (against undue influence) are both the other parties and their experts as well as the IIC of the NTSB. As far as I can see the current system works quite well