I personally believe temporary wound cavities at typical handgun speeds are far less significant than say a 223 round..
The US Army knew this all the way back to the Thompson LaGarde studdies at the turn of the 20th century. All the way back then they had determined that temporary cavity generally doesn't come into play until a projectile is moving about 2,000fps, and even then its kinda hit or miss...like everything else, it depends on where you were hit. If its only muscle tissue, the stretch cavity won't matter much. If it's less elastic material such as intestines, blood vessel branches, etc...then it can be a very big factor. What does it all mean? Well, you still have to place your bullets well, even at 2,000+ FPS.
