I just spent quite some time figuring why BTT started crashing. I wanted to disable certain keybinding for one application (iTerm2), so I bound the key to itself for this application. After that, BTT started crashing. I didn't think that I made a mistake, just assumed there was a bug in BTT but then stumbled upon a comment somewhere about the recursive checkmark.
I think it would be a better user experience if BTT warned about a potential recursive situation at least in obvious cases (key mapped to itself). Maybe BTT also should handle it better than just crash.
On a side note, is there a better way to disable a key binding for a specific app only?