Well, a call/cc saves the stack, but not the state. (My "VM snapshot" explanation was very bad in this regard.) If you allocate some memory and set it to a valu

Well, a call/cc saves the stack, but not the state. (My "VM snapshot" explanation was very bad in this regard.) If you allocate some memory and set it to a value, then save a continuation and change that value, it won't rewind to the old value when you invoke the continuation since the value isn't a part of the stack. Your points are true if you save that complicated data structure as local variables on the stack, though.