Let's review how BitTorrent works.
1. You create .torrent file from original content. The .torrent file contains crypto strong hashes of the original content.
2. You distribute .torrent file through website, mail or some other mechanism.
3. User's download content as described by .torrent file.
4. BitTorrent checks hashes in .torrent file.
The weak link here is step #2. User's don't have a strong guarantee that the .torrent file is the one you generated.
Note that this weakness is identical to direct download. Users do not have a strong guarantee that downloaded file named X is identical to the original file X.
You can make a stronger guarantee in the direct download case by using https, but the same holds true for distributing the .torrent file.
Just to be clear, you create the .torrent file containing the hashes and you distribute the .torrent file containing the hashes. The weak link is in the distribution and that weak link is identical to direct download.
By singling out this issue with BitTorrent, you lead readers to believe that this is a weakness of BitTorrent compared to direct download. There's a lot of FUD about p2p. It's sad to see that you are adding to it.