Is Programmed Instruction for Extension?

Although programmed instruction (PI) has been around for several years, it hasn't been used much by Extension. Recently, there's been more interest in this instructional approach. McKay discusses the use of PI in Extension from the point of view of using it more effectively. He mentions several examples of how Extension is using PI; then he discusses the advantages and disadvantages of its use. And, he cautions that there are times programmed instruction shouldn't be used at all.