Here is the orignal as stored by http://perlmonks.thepen.com. In a nutshell, my typo was comparing $b->[1] to $b->[1] instead of $a->[1]. Hope this does not lead to more confustion. ;)

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)