Pharmacoapple,
I hope your MBP stays good.
Regular hard shut downs will damage your hard drive for shure.
But hard shut downs have absolutely no influence on the hard drive cable.
Perhaps you had a doa cable.
But it's more likely that you damaged the cable yourself when changing the old hard drive for your SSD.
The cable neither the hard drive have absolutely NOTHING to do with the sleep mode problem.
It is a bug in the graphic driver or somewhere in the graphical user interface of the OS
(as I mentioned before).
Re-installing OS Mountain Lion will not help.
The only easy workaround temporary solution for 10.8 is still:
to set the sleep mode into 'never',
untill Apple releases a working update.
By the way: the mentioned sleep mode problems DON'T appear on the newst 21,5 and 27 iMac's 2012/2013.
And they don't happen either in 10.7.5
Best regards,
Danny