Not necessarily. The attack position originated in MX as a strong stable stance that lets the bike move underneath you with good bike body separation, and gives good control and confidence. The RR stem through its independent testing process, trying multiple heights and offsets over a couple years, has ended up putting the rider's hands at a stack and reach that happens to be practically the same as what you would find on a MX bike. That same attack position can now be used properly on an mtb.