It is undisputed, and should be indisputable, that a trial court's responsibility to the child cannot be abdicated to any parent, any expert. That heavy responsibility mandates that a court is not bound by any agreement between parents, nor by the opinions of any expert or group of experts. See Sedell v. Sedell, 100 So.2d 639 (Fla. 1st DCA 1958); Bolton v. Gordon, 201 So.2d 754 (Fla. 4th DCA 1967). Nor can this court substitute its opinion for that of the trier of fact. Adams v. Adams, 376 So.2d 1204 (Fla. 3d DCA 1979), cert. denied, 388 So.2d 1109 (Fla. 1980); Smith v. Smith, 55 So.2d 735 (Fla. 1951). However, the rationale for such rule is the ability of the trial judge to observe the demeanor and personalities of the parties and witnesses, to discern delicate vibrations and hidden influences, and to interpret nuances that are invisible in a cold record.