"Instead, you must aim for and click specific blank areas between the various navigation items. This reduces usability and also obliterates accessibility for us

"Instead, you must aim for and click specific blank areas between the various navigation items. This reduces usability and also obliterates accessibility for users who have less dexterity." I highly doubt that, given that the standard size for the dragging bar on in OS X is only 22 pixels tall, while the bar on the Mac App Store appears to be about 54 pixels tall. The increased vertical size would seem to make up for the smaller horizontal draggable area, from an accessibility standpoint.