I believe (and hope Klinsi has the team also believing) that this is a load of crap. There's been huge turnover in both teams since 2010 (15 new players in the Ghanaian squad, 16 in the USA squad) and almost no players left who were involved in that 2006 match (just Asamoah Gyan, Michael Essien, Sulley Muntari, Howard, Beasley and Dempsey still in the squads, of whom only Essien, Beasley and Dempsey actually played in 2006). Two matches, one four years ago and one eight years ago, aren't nearly enough to establish any kind of a pattern.
And, like I said, hopefully this is exactly what Klinsmann is telling the team. There's no reason they should be "in our heads".