Without touching uTorrent, I opened a newly downloaded torrent file from Pirate Bay. It shows as a Vuze file on the desktop and opens Vuze when clicked on. Perhaps you'll believe me now?
Since I don't need it any longer, I uninstalled uTorrent with Revo Pro, ran CCleaner, rebooted, checked the .torrent defaults in two places in Windows CP and then ran "The Third Man" search in Bit Che I mentioned earlier. Using the context menu to Save or Open on any result returns some quick program action, but nothing opens. Double clicking the entry brings up a box that shows Magnet button on the lower left, but it opens nothing. Running a different search, such as "On the Road," and opening a result brings up a box with Torrent on the bottom left. That opens Vuze. Why not a magnet? From torrent websit site, e.g., Pirate Bay, it does open a dialogue box and Vuze?
Btw, Bit Che still doesn't show Vuze among the "Open Torrent With" choices, just the three mentioned earlier. However, in Bit Che Preferences, it says "Azureus client detected" at the bottom.