Correction for @ coercer

- It does more than just remove the Scalar
- Show <> decont methodop
- Show a bug where using `@` instead of `<>` leaks memory

doc/Language/containers.pod6

@@ -283,11 +283,20 @@ As hinted above, scalar containers prevent that flattening:
     my @a = 1, 2, 3;
     say f $@a, 4, 5;            # OUTPUT: «3␤»
 
-The C<@> character can also be used as a prefix to remove a scalar container:
+The C<@> character can also be used as a prefix to coerce the argument to a list, thus removing a scalar container:
 
     my $x = (1, 2, 3);
     .say for @$x;               # 3 iterations
 
+However, the C«<>» is more appropriate to decontainerize items that aren't
+lists:
+
+    my $x = ^Inf .grep: *.is-prime;
+    say "$_ is prime" for @$x;  # WRONG! List keeps values, thus leaking memory
+    say "$_ is prime" for $x<>; # RIGHT. Simply decont the Seq
+
+    my $y := ^Inf .grep: *.is-prime; # Even better; no Scalars involved at all
+
 Methods generally don't care whether their invocant is in a scalar, so
 
     my $x = (1, 2, 3);