Two with One Blow does not mean anything as written, because a Master Thrower can't get the ability to attack two adjacent foes from the Master Thrower class. It can be interpreted to mean she is granted this ability, but a much simpler solution is to insert the words "one of" before "two opponents" in the first sentence to read, "If a master thrower with this ability uses a thrown weapon to attack one of two opponents adjacent to each other,...". There is no known errata or FAQ on this, and this functions in almost exactly the same way as granting the ability, but doesn't completely disregard the structure of how the text was written.