1. the user does not want a syntax dump on their screen
Forgot to say that this will be only showed for developers.
You just create a new config variable called "server_type" or "server_status" or whatever with 2 possible values, "Production" or "Test". Then if the server is a test mode then you could see all the debug messages.
2. this could be exploited eventually?
Since the code is public (google code) anybody can see all the sql queries of the system.
It worth the time, unless you know every position of every sql query in the system. This is very useful for newcomers and if you want that the community report bugs more accurately , develop new features, bla bla etc