παρὰ τὴν θάλατταν: also effective in the portrayal of the seaman's unpretending nature.
ἐν μετρίῳ σχήματι: with unassuming carriage, has nothing to do with the dress, but merely with the deportment (cf. above, προσεσταλμένη). Perhaps there is a slight hit at Gorgias' pompous manner. See Introd. § 5 end
19 f.
λογίζεσθαι ... ἐπίσταται: naturally not meant in full earnest, and not without some color of irony. The change of tense in ὠφέληκε and ἔβλαψε is probably due merely to the frequency of the form.
20 f.
οὕστινας ωφέληκε κτἑ.: reminds us of Matt. xviii. 6, where of those who offend it is said: συμφέρει αὐτῷ ἵνα ... καταποντισθῇ ἐν τῷ πελάγει τῆς θαλάσσης.