I understand and agree.  I don't think I explained myself very well.  When I make this change and run specs I get the following error: `acts-as-taggable-on/spec/acts_as_taggable_on/taggable_spec.rb:495:in `block (2 levels) in <top (required)>': undefined method `supports_concurrency?' for ActsAsTaggableOn::Utils:Module (NoMethodError)`.  This is because module instance methods are not callable.  There is a good write up on the options here http://elhumidor.blogspot.com/2008/09/cleaner-utility-modules-with.html .  I forgot about `extend self` until I read that post.  For this situation I think it is appropriate.