In other words, despite its tremendous success when applied, currently PSI is not widely adopted or even widely known. Why? Sherman (1992) suggests two reasons.
(1) "The educational establishment is enormous, the constituencies are multiple and diverse, often with conflicting interests. The barriers to educational reform are formidable, even awesome. The power, money, the investment in keeping things as they are may be impossible to overcome. Recommendations may be acceptable as long as they don't change things very much." (p. 61)
As you can clearly see, PSI does represent a significant change in the way in which education is conducted. In fact, Keller's (1968) seminal article on PSI was called "Goodbye, teacher..." Sherman notes that "[s]ome PSI courses have been prohibited in spite of their success" [emphasis added], and he tells the story of an example in the Psychology Department at Georgetown University.
(2) "What happens when someone decides to make changes, for example to grade each quiz, allow only two attempts per unit, restrict self-pacing to the point at which a unit must be passed each week...Suppose such a course is a failure. Is it an instance of PSI failure?" (p. 62)
Gallop & Allen (1996) take this point one step further and suggest that variations of PSI may have given it a bad name. They write: "[F]aculty members, psychologists and others, began offering 'PSI' courses without knowing what they were doing; when such courses were not very successful, the PSI method was blamed rather than its implementation" (p. 4).
The article by Gallop & Allen (1996) suggests yet another reason. They reviewed two books very likely to be used by teachers of psychology and found that, for whatever reasons, PSI was misrepresented and marginalized. If this is the norm, then it is not surprising that teachers would be unimpressed with the PSI method.
The news is not all bad. Michael (1996) reminds us that the PSI story is not yet over.
Today various educators throughout the world continue to use PSI and actively promote it. Some college instructors have "updated" PSI, by incorporating computer technology into the system (Crosbie & Kelly, 1993; Pear & Novak, 1996).