Fluids can be conditioned by pumping through a Tubing Shear History Simulator to match the shear rate and time at shear found in the tubulars before the fluid enters the fracture. Shear history simulation can be accomplished by the recommended ISO procedure or can be tailored to match specific well conditions. Crosslinker is injected on-the-fly to match actual job conditions as closely as possible. For deepwater applications, the temperature history in the tubing can also be matched. After the fluids are conditioned in the tubing shear history simulator, they are dynamically loaded into the Chandler 5550 viscometers.