Hello! I wouldn't be too worried yet, it all changes in different stages, he is just a toddler experimenting now. Kids that age love to experiment with the whole "what will happen if..." and unfortunately that stage lasts for a while. That is true of some ND children as well, not exclusively gifted children. But I find that most gifted children are quite curious about everything and part of that behavior is part of the curiousity. That being said, they also pick up on all reactions, not just consequences...so be aware of any reactions to those behaviors as they may keep up a behavior just to see the look on your face, or to hear a sound you make, etc. : ) Fun, huh? I do like 1-2-3 magic. I like lots of books when you pick and choose the parts you like the best. I teach parenting classes and have read tons of different ones. I am in the middle of the book Transforming the Difficult Child, also enjoy the whole love and logic approach and common sense parenting...so many great books and resources are out there. Good luck!
Michelle