default to mysql install breaks infrastructures that set node attributes via recipe instead of role?

I haven't gotten time to dig deeply into this, but here at yetu, we set node attributes in cookbook recipes rather than in roles.  I think that by defaulting to certain actions in the cookbook we are making it hard to override these attributes in a sane way - so my proposed fix is to set the attributes to 'nil' by default, encouraging users to set the attrs in their own site-specific cookbooks/roles/environments.