"Matt Whiting" wrote in message
...

Is this an "official" FAA procedure or just something that most
controllers understand as an indication that FF will be requested?


Depends what you mean by "official", I suppose. I've never seen anything in
print about filing it through DUATS as I explained here, I just tried it one
day and it worked. The entry of VFR flight data into the NAS computer is
certainly "official", the procedure is described in the flight data
processing manual.