yeah, actually timeout of zero is what you'd typically do if you're just going to quit.  you'd want to allow a timeout before killing the stuck process if you were being aggressive.

and the problem that happens is you get a 'stuck' chef-client process that /never/ will return and all the subsequent chef-client runs will stack up behind it.  NFS problems are a great way to generate stuck processes like this and having this blocking chef-client behavior means that a stuck NFS mount turns into an OOM condition or another resource consumption problem.  its an edge condition, but across all of our users, its a condition that we're just about guaranteed to find somewhere.  this isn't going to happen in the happy case when chef-client is running correctly.