Trautman's role in the first three movies is pretty much as Rambo's barker. He's always talking him up. And while Rambo is admittedly like, the awesomest warrior ever, one can't help but think he employs Trautman as part of his psychological warfare approach so his arrival will be heralded with fear rather then determination.
pretty clever of Rambo really, but hey, we know he's the man, he'll eat stuff that'll make a billy goat puke.