Say what???? You mean people actually take these things offroad?????
Simply put: when offroading, you have the potential to expose your vehicle to non-typical forces, stresses and demands that CAN increase the likelihood and propensity for damage and mechanical failure.
What dramatically seperates the H2 from a built-up Tahoe is that the H2 was designed & engineered extra strong in order to encounter these extremes and keep within a safe range of reliability and function. In other words: it can handle a lot of harsh stuff...but nothing is impervious to failure.
I firmly believe that when approached properly and in a conservative/reasonable manner...off-roading will not cause problems.
Time and again I've seen excessive speed, poor judgement and inappropriate actions result in problems. Aka....driver error.