I read this as indicating the objective is "to characterize the effect of transmitted road vibration." Developing a system is merely the means to achieve that end. And if the study 'to characterize the effect of transmitted road vibration' is going to do so by measuring the rider performance with varying degrees of transmitted road vibration it's not much of a leap to conclude that they are looking for a cause and effect relationship with the cause being the level of transmitted road vibration and the effect being a change in rider performance.

Will they technically prove such a relationship? No, but by holding as many other factors as possible constant (same rider, same position/fit on bike, same wheels & tires, same saddle & pedals) their conclusions will almost undoubtedly be that any significant change in rider performance that correlates with variations in transmitted road vibration is in fact an effect of those variations. Otherwise they will not have achieved their objective to "characterize the effect of transmitted road variation."