Taken in isolation, the sentence may be offensive. In context, having seen MJD in person, speaking at various YAPC::NA events, the comment is quite apt, and consistent with his views about craftmanship as it applies to software development.

The law has a term called equitable estoppel which essentially means that if you discover someone's breaking a deal, you have to take action within a reasonable period of time. PodMaster's been using that quote in his .sig for ages (I think someone said about a year) -- it seems odd that you didn't feel the urge to complain about it until now.

And offering your module to block the offending text is an odd non seqitur -- if it really offends you, disable the signature block on your User Settings (as already suggested).