You don't need to be a confirmed Lacanian to realise that to read an email is, already, to misread an email. One could evoke the old Russian formalist distinction between fabula and syuzhet: there is the actual bare words of the email itself (syuzhet), and then there is the story, and the affect, we interpret and, in a sense, invent ourselves, from these words (fabula). As in film, the two can never fully coincide, nor do we have any guarantees that that latter conforms in any way to the author's intentions. In a film, it could certainly be argued, this does not matter. With Stanley Cavell, we can argue that the filmic object is what we remember of it and how we interpret it. When dealing with emails, this presents fairly obvious practical problems.
Will Schwalbe and David Shipley, authors of Send: The Essential Guide to Email for Office and Home (a book which I have not read, so please forgive me if I repeat anything they say) are fond of saying that "email is an affectless medium" and offer various tips for better, friendlier, more productive, email communication. But why should this be so? Why do we need to overcompensate for the coldness of electronic communication with emoticons and multiple exclamation marks? Why is it so hard to imagine a book of the collected emails of some great author, poet, or statesman, when so many similar collections of 'snail mail' letters exist?
I suspect one reason is the way email simulates intimacy. Its model has really never been the letter, and it is rare to apply the formal rules of letter writing - even to a complete stranger - that come so naturally when using the postal service. When writing emails, we tend to write as though we were talking ("Hi, how's it going?" scarcely "Dear Sir,") and so we read as though we were listening. Email fakes an imaginary presence which tends towards the illusion of making the medium seem invisible, whereas a letter will always remind us of its own frame. When reading, we tend to superimpose a tone of voice - and almost inevitably a different tone of voice to the one with which it was written - onto an email without thinking about it. This then skews our understanding, creating a kind of paranoid hermeneutic which would be quickly dispelled if we were talking in person (due to cues - themselves as good as invisible - such as tone of voice, facial expression, etc.).
Yet, despite all the formal signs to the contrary - the dear sirs, the letterheads, the yours sincerelys - a handwritten letter actually is more intimate. For even without any understanding of graphology, a letter retains the mark of the body (it's grain, if you like, following Barthes) - the slope of the characters, the pressure on the paper, little crossings out - all speak to us directly from the fingers whether we consciously realise it or not. We can pour our heart out in a letter, somehow we can only vent spleen in an email. And it wouldn't take much surfing (pick a message board or a comments box at random to see what I mean) to find evidence that this problem of false, forced directness is far from restricted to email, but infects almost all web-based communication.
Then again, perhaps behind my words (and those of Messrs Shwalbe and Shipley), there is an implied idealist vision of communicational utopia, wherein, if only we all understood the medium better we would all just get along fine and all the world's problems might be boiled down to a simple matter of misunderstanding. I can't help thinking of the Babel fish from The Hitchhiker's Guide to the Galaxy, which, by removing all barriers to effective communication between different cultures, causes "more and bloodier wars than anything else in the history of creation". The crucial thing, perhaps, is to recall, with Lacan, that we understand the other's speech best when we recognise the impossibility of our own understanding, the necessary and constitutive gap which makes any communication possible.