scook
I was under the impression that once the error is detected, a flag is set in the project and it does not ever get reset. If the warning message is a problem, it can be suppressed by setting WarnSilentBuses to 0 in Preferences > File > Initialization File. To get to the "Initialization File" setting make sure the Advanced radio button is selected at the bottom of the Preferences dialog.
No there is no flag for this. Damn scook you actually got something wrong :)
Its dynamically detected by looking for any outputs or sends that go nowhere. i.e "--None--". When that happens its normally not intended and you could have some tracks in your project not sounding.
That is the sole reason for this warning. in 90% of the scenarios its something like this which is why we have retained the warning message. I asked in the forums some time ago and people voted to leave the warning in since it serves a useful purpose sometimes :)