Critical to advanced social intelligence is the ability to take into consideration the thoughts and feelings of others, a skill referred to as Theory of Mind (ToM) or mindreading.  In this article, we present a critical review of the comparative methodology and utility of the nonverbal FBT along with a description of an attempted FBT replication conducted with a bottlenose dolphin prior to the implementation of the more successful approaches used currently. Attempting to replicate Tschudin’s (2001, 2006) methodology with dolphins highlighted several flaws that may explain the failures of socially complex mammals to display competency: (1) reliance on a containment invisible displacement procedure that is difficult for non-human animals and especially dolphins to follow, (2) a complex procedure which demands extensive training time, (3) a long trial duration with several moving parts which taxes the animal’s memory and attention, and (4) a restricted number of two-choice FBT test trials, which limits statistical power given the small pool of trained animals. Although recent research paradigms for primates have corrected for some of these flaws, it is critical that comparative psychologists address these limitations for other species or taxa to be tested validly.  Future research in ToM understanding through a false belief approach should move toward more ecologically valid designs and appropriate implicit measures that facilitate comparative approaches that can be replicated.