I try to leave a note but sometimes I just got nothing to add and I will then vote anyway. A lot of really good hubs are so well done all you could write is something like "ditto". Often I only write a short comment, just to say howdy and show my support.
Your hubs really get me to thinking without really having something to add to the discussion.
I am happy to get a view with a vote.
With all that said there are some unkind people here who just visit to vote down on a hub. Bummer for them not you.