- if the best this is is a revision aid, that's an expensive revision aid.
- if this would be useful for students who missed the lecture for some reason, cant they do what anyone else has ever done, get the summary or notes from a peer and do some reading around.
- £ for £ there is an almost infinitely greater value for lifelong learning in a simple reference list at the back of an appropriate journal article than there is in a recorded lecture. This also goes for other suggested uses, like recording a summary instead of the whole lecture or recording a 'pre-reading'
- if we are aiming at students' epistemic fluency, this only encourages them to rote learn - evidence the statistics that say the traffic sky-rockets at exam time.
- how does a recorded lecture encourage them along the cognitive apprenticeship road to mastery in the given discipline?
- if we want to keep ephemeral lecture speech lively, how much will knowing your every word is reified prevent you from doing things 'on the fly' that may afterwards seem unprofessional?
- limiting the potential audience to just our students (who login to blackboard - assuming they can!) is naff and old hat.
- what is a lecture good for anyway? If your lecture is the same every time then you probably shouldnt be giving it as a lecture. The students in a lecture have given ceded some level of pedagogic control over to you, they're giving their attention to what you have to show and say - will they do that at any other time (in competition with, for example, their chores or family/social time). I would not think anyone would want to review my lectures because they do not contain much raw 'content' - the objective is to stimulate them to think - for that limited time that they have volunteered their attention to what I have got to say...
There is a clearer case for providing canned lectures to disparate distance students, but, even there, I would be feeling towards only making them available for a limited time.