How do I get a tighter grid for MIDI editing in GarageBand 10? In the previous versions of garageband, when I double-clicked on a region and the editing window on the bottom popped up, I could use the ruler button to choose how tight the quantize grid was.

In a 2016 update I don’t find this control in the same place. 

How can I change that timing  grid now?
You can!  But the feature is different than before.  To get a smaller grid you can click the arrow at the right side beat/tempo/key led area and select "time".