Thanks for the other data points.

I always hear comments sort-of-out-loud though, the same way reading happens sort-of-out-loud-in-my-head. I don't think it's something I can switch off. I always hear tone and it would confuse me not to, even though I do sometimes get it wrong. In fact, I get confused if people I'm close to type without punctuation, since an absence of tone just registers as "the tone of being distant and brusque".