If by "bug fix" you mean "totally useless, horrible design choice that ruins the Super Strength set for defense based characters" then yes, I would agree.
There are any number of directions this could have been taken -
Make it non-stackable
Increase the recharge length so it cannot be made perma
Covert it into a Build-Up click
Etc. Etc.
The -DEF debuff totally destroys using SS with defense based sets. Instead of adding more choice and customization (eg. fun), this change is taking choices away in my opinion. Not worth the time investment to level a SS character using Shields or SR or whatever defense based set, grinding for IOs, Incarnates powers and such when the set includes a nonsensical debuff that essentially guts all of that effort.
Sorry, but no thank you.