Parallel Processing and Multitasking - Good or Flustering?

The concept of parallel processing has often been talked about, or in other words, multitasking. The underlining message or belief is perhaps that this is some kind of greater efficiency of working. Even I find now that I cannot do without two screens for my computer - it makes it easy to work between programs or documents. Doing several things concurrently is meant to be good.

Where does this concept come from. The alternative idea is that carry on with one task, and that task only, until it is completed! You are not distracted! The job gets done and out the way, whereas with the parallel approach it is more difficult to keep a trace on what you are doing and to finish things, and you simply end up just getting befuddled, confused and flustered, however you avoid the boredom of doged pursuit in the one task approach.

I suspect that for me the idea of parallel processing comes from perceptions of computing and the way that the brain is perceived to work....you can only instantly recall 6 or 7 numbers immediately after they are given to you, therefore the conclusion might be that the brain can parallel process at just about these levels. However, we are talking about numbers here and short term memory, not complex tasks.

There is a sense that if parallel processing does occur is largely automatic or semi-automatic and the skills do not necessarily interfere with each other too much. Driving a car (largely kinesthetic and visual) can be carried on whilst listening to the radio (purely auditory). It is more likely that the parallel processing we talk about in work is simply rapidly shifting to and from different mediums, tools and content, in small chunks rather that co-carrying a number of tasks and activities simultaneously. The danger is that if you try to handle too many of these things simultaneously you might become flustered and in the end focus your energy into one area, or redistribute your time in manageable chunks.

In distance education if students have to handle to many different types of thing more or less concurrently this might become somewhat overwhelming and pose a problem to their learning.