If the alternative is to read the textbook or view an online mini-lecture before coming to class, which if any would students prefer? Do students respond by upping their participation rate if instructors do some just in time teaching by surveying students asking for some open ended feedback as well as giving them some closed ended questions to test their understanding?
We are having some early success with doing both sorts of things together with non-residential students in our Professional MBA and Executive MBA programs. They like that the live class time is customized to the questions and issues they've expressed prior to class and the online mini-lectures ahead of time are more accessible to them than the textbook, plowing through the book is hard work that some don't do.
Just in Time Teaching could be made even easier if instructor who teach the same class, but perhaps at different institutions, shared in the creation of the mini lectures. That would lessen the burden on the individual instructors. I wonder if we'll see that happening in the near future.