My problem:
Healing brush did not work in Photoshop CS6 with Wacom Intuos-2 under OSX 10.8.5 Mountain Lion, MacBook Pro 9.1.
Wacom's suggested procedure reported by sthoy made me aware that I never updated drivers without removing the old stuff first and without using that removal application from Wacom in my program-folder.
So I repaired permissions - restarted - removed the existing driver 6.1.7-5 - restarted - reinstalled driver 6.1.7-5 from the .dmg file.
And now everything incl. the healing brush work fine.
I have also tested newer drivers … they all result in an empty tablet-window when I clicked on the tablet-symbol in system-preferences.
I also looked through the packages of the latest driver 638-2. As far as I could see there were only codes/references to Intuos-2-pens and brushes but when I look for example through the help files they were only covering Intous-5.
So my conclusion: Version 6.1.7-5 is the last Wacom driver working with Intuos-2 provided one follows procedure suggested by Wacom