Correcting an error and expanding

doc/Language/classtut.pod6

@@ -82,16 +82,18 @@ my $eat =
 $eat.perform();
 =end code
 
-In this case, C<BUILD> is needed since C<bless> calls it with the two positional
-arguments. With its signature, C<BUILD> converts the two positionals to the two
-attributes, C<&!callback> and C<@!dependencies>, and returns the object (or
-turns it in to the next phase, C<TWEAK>, if available).
+In this case, C<BUILD> is needed since we have overriden the default new.
+C<bless> is eventually (after calling C<BUILDALL>) invoking it with the two
+named arguments that correspond to the two properties without a default value.
+With its signature, C<BUILD> converts the two positionals to the two attributes,
+C<&!callback> and C<@!dependencies>, and returns the object (or turns it in to
+the next phase, C<TWEAK>, if available).
 
 Declaring C<new> as a C<method> and not a C<multi method> prevents us from using
-the default constructor which uses the attributes as named parameters. That is
-one of the reasons why using C<new> is discouraged. If you need to declare it
-anyway, use C<multi method new> if you do not want to disable the default
-constructors.
+the default constructor; tis implicit constructor uses the attributes as named
+parameters. That is one of the reasons why using C<new> is discouraged. If you
+need to declare it anyway, use C<multi method new> if you do not want to disable
+the default constructors.
 
 =head1 Starting with class