Myfeeling is: tools are designed for specific tasks, and while a screwdriver may work as a chisel for a short time, it's not designed for that use, and is prone to sudden failure when subjected to that kind of abuse.
It's one thing to use a screwdriver to pry out a staple, or to dig out a bent nail until you can grab it with a pair of pliers, it's another thing to use it in place of a proper pry bar.
Ditto for dikes..
There are many types of dikes, designed for cutting different materials.. In general, the thinner the cutting edge, the cleaner the cut, and the softer the material.
The 5" pair of semi-flush cutting dikes that I use on the bench are a far cry from the 6" or 8" dikes, or the 7" end-cutting pliers in the toolbag.. I wouldn't dream of cutting 12 THHN with the 5" dikes.. nor would I use the 8" dikes to cut 24awg hokup wire..
I do use a screwdriver handle as a lightweight mallet, when I just need to induce some vibration, but I don't use it as a hammer, and I've been known to use a crescent wrench handle as a lever..
