Setting group on the nsd command line doesn't necessarily work correctly. Is there a reason you need /home/dude/web/icann owned by 'dude', but nsd is running as 'nobody'? It is my experience that the user (not group) that nsd is run as must own the files nsd needs to write.
As to the merits of daemontools, that response didn't answer the question, and, in this case, just converting over to daemontools without correctig the underlying permissions issue isn't going to help anything.
