Aggrevation, thy name is tension

Tension is important in weaving, especially even tension on all strands. If you don't have even tension on all strands, it looks like this--

--and you can't pass a shuttle with the weft through there with anything like your normal speed.  This makes the weaving very slow.  And this is AFTER tightening the warp eleventy-million times.
  So I do this--

Chopsticks, pencils, pens, and fishing weights hung from paper clips.
  Ugh.  So frustrating.