Yes, he isn't a Godín-style stopper, that's true. However, what made Boateng valuable for Bayern was his ability to win the ball quickly and cover large distances with his speed. His main strengths were his ability on the ball, his comfort in marking opposing players, his ability to step up and apply the pressure/win the ball, his heading, and his speed that helped him cover the distances. I'd have been okay with him had he just had to deal with Bebeto, but both Bebeto and Klinsi, especially Klinsi, and then there's Möller drifting around with one of Hierro and Baraja making late runs into the box as well...Boateng wouldn't really thrive in this sort of a setup. He'd thrive better in a setup where he can isolate attackers and close them down quickly, in a setup where he can have more of the ball than not, in a setup where he can make the most of his strengths, and EAP's team wasn't that.