The unfortunate thing is
I have worked in places where they literally mean 3 to 4 things at the same time. While I do not disagree with your point of working on another simpler task while another is in a hands-off mode. What most people associate with multitasking, and have been subjected to, is not the case you present.
It is those cases where you are expected not only to have answers to questions from other people whom you asked two days ago (and are following up), but you have to have 5 to 6 other tasks (that are always critical when only 1 or 2 actually are) done two days ago, all the while trying to look into issues affecting 3 or 4 other systems that are totally unrelated to each other. Did I mention all of these should have been done about 15 minutes after they were assigned because after all it they are nothing more than 10 minute tasks. >.
I know this is an absurd example, but it describes the last job I worked pretty accurately. =D
