What's problematic is that, according to this University of Chicago study, people consistently overestimate their ability to convey tone in email. Check out this Lifehacker post about the study. To boil it down:
The reason for this communication disconnect, the researchers find, is egocentrism...Think about. We are more and more chosing modes of communication which are easiest because they leave the other partner out; they begin and end primarily with the "sender". We don't have to (immediately) respond and alter our tone, pace or choice of words, to be understood by the "receiver." Unfortunately, with email it is all about ME. When communicating let's try to pick the most effective modes first.
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