the best counter attack against fried liver
The Wilkes-Barre variation (or for those who don't mind revisionist re-naming the Traxler Counterattack) is indeed excellent and probably winning for Black if White plays 5. Nxf7? The problem, as with so many gambits, is what to do against a more modest, less "show me", reply. For many a long year (this fifth move recommendation is from amongst others Paul Keres, Svetozar Gligoric, and Y. B. Estrin) anyone above a certain grade will find the following.
(Largely analysis by Estrin)
How to avoid a "Black is worse" outcome in lines with 5. Bxf7is problematic. Misplaced King, difficulty with achieving full development. Spells trouble.