The results of Experiment AIIE1 support the hypothesis that foreground occlusions increase reported presence. Further, they suggests that a foreground occlusion mounted in an HMD may be of practical benefit for increasing presence.
While Experiment AIIE1 found a large difference between conditions, the possibility existed that the results were due to subtle cues picked up from the experimenters. Experiment AIIE2 was a replication of Experiment AIIE1 which controlled for this possibility, by using an experimenter blind to the hypothesis.