re: Table top rehab

How clean is the break?  Did the glue fail or did the wood break?  Often the wood fails before the glue does but you can get both so you have to assess.  If there is exposed glue, you probably need to rejoint the edge because with the exception of hide glue, most wood glues will not adhere to old glue.  If the glue held but the wood failed (and there is no exposed old glue) it may be possible to simply glue it back together.  If you dry fit it back together, you can check to see if there are any piece chipped out.  If there are, then planing or jointing the edge may give you a better looking joint.

And as noted above, do not glue the battens back to the bottom,  they should be attached with screws with elongated holes in the battens to allow for wood movement.