[nickpsecurity]

Hmm. You could use those as examples. There would be cases where type punning might be true in developer time. There would be cases where self-modifying code might buy you better memory or CPU efficiency. Yet, self-modifying code is pretty hard to do and do right for most coders that I've seen. Type punning happens automatically in dynamic, safe language with decent conversion rules. You often only do the conversion rules once or when you change the class/type but you mentally do that in your head anyway if you're analyzing for correctness. Difference is you typed it with conversions being mechanically checked.

These you bring up seem to be double-edged swords like the others that can have about no negative impact or significant one depending on context.