Lynne Truss reports similar claims from her vox pop in Eats Shoots'n'Leaves:
Now, there are many people who claim that they do fully punctuate text messages. For Cutting a Dash, we asked people in the street (outside the Palladium Theatre, as it happens, at about 5pm) if they used proper punctuation when sending text messages, and were surprised – not to say incredulous – when nine of out ten people said yes. Some of them said they used semicolons and parentheses and everything. [...] But do you know what? I didn't believe those people. Either they were weirdly self-selecting or they were simply lying for the microphone.
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