Did the physical layout of the Duke buildings permit Hubert Pearce to observe the target cards during the Pearce-Pratt distance series?

C. E. M. Hansel examined the buildings in the 1960s and argued that a route existed by which the subject, unobserved in the library, could have reached a position from which the cards were visible. Rhine and Pratt disputed the sightlines, the timing, and whether such an absence would have gone unnoticed. Neither side conceded, and the buildings have since been altered, so the question can no longer be settled by inspection.