The key word in the caption is perhaps "fine."  He showed a fine disregard of appearance as he stripped in front of the other men.  He isn't slovenly; rather, his disregard here is splendid.  The implication seems to be that a fine regard of appearance and a fine disregard of appearance are two sides of the same coin.  He knew how to look good in clothes and, commensurately, how to look good out of them. From A Slip in the Fens, 1873.