Any by the way: Because no user code needs the $dbh->quote() method in "paranoia mode", DBI should warn or die when non-DBD code calls this method.
Agreed, and I'd even take the extra step of saying that
->quote() in user code should be seriously considered for deprecation, "paranoia mode" or no. There may be some valid case where it's needed that I haven't encountered, but it mostly just seems to be used by people coming from PHP and looking for an equivalent to
mysql_real_and_for_true_escape_string_i_really_mean_it() because they can't be bothered to learn how to use placeholders (or, in the case of one individual I've argued the point with a few times, are convinced that placeholders are The Death Of Performance).