Realized that DESTROY was clearing the cache, which was wrong.

lib/DBIx/Connection.pm

@@ -27,12 +27,12 @@ CACHED: {
             _svp_depth => 0,
         } => $class;
     }
+}
 
-    sub DESTROY {
-        my $self = shift;
-        $self->disconnect if $self->connected;
-        delete $CACHE{ $self->{_key} };
-    }
+sub DESTROY {
+    my $self = shift;
+    $self->disconnect if $self->connected;
+    return $self;
 }
 
 sub _connect {

lib/DBIx/Connection/Driver.pm

@@ -54,8 +54,38 @@ __END__
 
 DBIx::Connection::Driver - Database-specific connection interface
 
+=head1 Description
+
+Some of the things that DBIx::Connection does are implemented differently by
+different drivers, or the official interface provided by the DBI may not be
+implemented for a particular driver. The driver-specific code therefore is
+encapsulated in this separate driver class.
+
+Most of the DBI drivers work uniformly, so in most cases the implementation
+provided here in DBIx::Connection::Driver will work just fine. It's only when
+something is different that a driver subclass needs to be added. In such a
+case, the subclass's name is the same as the DBI driver. For example the
+driver for DBD::Pg is
+L<DBIx::Connection::Driver::Pg|DBIx::Connection::Driver::Pg> and the driver
+for DBD::mysql is
+L<DBIx::Connection::Driver::mysql|DBIx::Connection::Driver::mysql>.
+
+If you're just a user of DBIx::Connection, you can ignore the driver classes.
+DBIx::Connection uses them internally to do its magic, so you needn't worry
+about them.
+
+=head1 Interface
+
+In case you need to implement a driver, here's the interface you can modify.
+
+=head2 Constructor
+
 =head3 C<new>
 
+  my $driver = DBIx::Connection::Driver->new( driver => $driver );
+
+Constructs and returns a driver object.
+
 =head3 C<ping>
 
 =head3 C<begin_work>

t/base.t

@@ -2,7 +2,7 @@
 
 use strict;
 use warnings;
-use Test::More tests => 93;
+use Test::More tests => 92;
 #use Test::More 'no_plan';
 use Test::MockModule;
 
@@ -71,7 +71,6 @@ ok !$disconnect, 'Disconnect should not have been called';
 ok !$rollback, 'And neither should rollback';
 
 ok my $new = $CLASS->new( 'dbi:ExampleP:dummy', '', '' ), 'Instantiate again';
-isnt $new, $conn, 'It should be a different object';
 ok $dbh = $new->dbh, 'Connect again';
 $dbh->{AutoCommit} = 0;
 ok $new->DESTROY, 'DESTROY with a connection';