Fred Gambit Success
The following game illustrates that the Fred Gambit is playable against a strong opponent as long as Black has done his homework and is completely fearless in the opening.
In this game White plays a fine game, and neither side plays perfectly. This is a very hard-fought game between two good players at a time limit of 3 days per move. Black has spent a lot of time studying the Fred Gambit and White has probably never faced it before (which is the typical scenario.)
I am not claiming that the opening is sound or that White shouldn't win with best play. If I am white and you play this opening against me, then I will accept both pawns with every expectation of destroying your position and grinding you into the dust! My point is simply that there is a very big difference between "sound" and "playable"!