A British thermal unit (Btu) is a standard unit of energy that is used in the United States and sometimes in the U.K.
There is another defect in tires that can cause a vibration called loaded road force variance. The tires and pass a visual inspection, a radial and lateral runout test, be perfectly balanced, but still cause a vibration. This is due to the internal defects in the tire.
Mis-torqued lug nuts, bent wheel, out-of-balanced tire are all causes of shakes when braking. Unless I missed it in your presentation and one of the most important tasks to prevent brake chatter or vibration would be to torque all the bolts including the wheel bolts. If the bolts holding the wheels to the hubs are not properly torqued they will cause vibration when you apply your brakes.