I bet I have an idea why. "$rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z) $+ $rand(a,z)" is lengthy compared to "$r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z) $+ $r(a,z)"

One solution would be to modify $rand so this could be done. $remove($rand(a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z,a,z),$chr(32)). Where $rand(a,z,1,9) would return "D 4" for example.