Letters that weren't clearly pronounced fell out, thus:
Futui puella formosa instead of Futui puellam formosam on the walls of Pompeii.
Even educated Romans, though, seemed to have elided words, such as the famous incident where Cicero says Crassus should have heeded the warning of the fig seller who was shouting out "cauneas!" (=cave ne eas).
Either way, I'll bet that the average Pompeiian spoke it better than the average Latin student of today.
ἡ δὲ κἀκ τριῶν τρυπημάτων ἐργαζομένη ἐνεκάλει τῇ φύσει, δυσφορουμένη, ὅτι δὴ μὴ καὶ τοὺς τιτθοὺς αὐτῇ εὐρύτερον ἢ νῦν εἰσι τρυπώη, ὅπως καὶ ἄλλην ἐνταῦθα μίξιν ἐπιτεχνᾶσθαι δυνατὴ εἴη. – Procopius
Ummaka qinnassa nīk!
*MySmiley*