It doesn't really avoid curves, though, even when carved into stone. Look at the inscription on Trajan's Column [1], f'rinstance; yes, it's got the classic U written as V, but the C, D, O, S etc are all as curvy as you could possibly want.
The Romans wrote most ephemeral stuff on wax tablets which could be smoothed over for re-use; this is where the phrase "tabula rasa" comes from. Some examples survive and also show curves [2].
