Bench top/apron joinery

I'm planning my bench as I've said. The top will be flat sawn boards standing on edge and face glued together, butcher block style. My question is about the aprons. I see these pictures of these nice dovetailed or finger jointed corners, but what about the movement of the wood? If I dovetail the front corners and glue them, then on the ends use a long M/T joint kind of tongue and groove style (not sure what that's called really) and pin it similar to bread board ends I think I'll be ok... but what about the back corners? If I dovetail them too then the top won't have anywhere to move. I could finger joint them and leave them unglued. Anyway what have you seen or what would you do?

Most of the pictures I've seen are amazingly unclear on this point.

Thnx

look at rob keeble's bench post he has a simple design that works for him.

Could you post pictures or plans of what your building. Its not exactly clear but I would attach the apron it at the front and allow the expansion/contraction to happen in the back. I wouldn't put any joints at the back and just pin it with a dowel from the bottom. After you drill the hole for the pin take the apron off and enlarge the hole into a slot so the top can move.