Curious if SETI ever "tests itself", like with perhaps (scheduled but
random) "blind tests".

I.e., someone "injects" a signal similiar to what is believed could be found
by ET into the data collection.  (Either at RF or data level, best would be
at RF level.)

The idea being to see if SETI will catch the fake ET signal, and if so how
long will it take.

Cheers,
Eric