Mobile excavating and bulk handling equipment must maintain a balance between agility and ruggedness. This balance is based on prevailing conditions. Agile equipment can be too fragile during loading and a rugged piece can be too sluggish in operation. In mining and heavy construction, difficult job conditions are termed “encumbered space.” These conditions are specified as to their material and geometric properties, with time and human factors effects included. Haulway sections and running surfaces are characterized, along with the bulk solid that is being moved, in an encompassing “total systems” context. Capacities and vehicle weights are examined and specific aspects of conditions are ranked with regard to their impact on agility and ruggedness. Specific weighting factors are also determined. A statistical-graphical method is introduced for determining power requirements for a piece of equipment. This is first done without regard to agility and ruggedness. The method is then upgraded to estimate their proper balance.