There's this long going notion that you cannot re-shape a muscle through trainig: what do you think about it?
No, you can't change the shape of your muscles without injury or surgery.
You can change the size, which can change the appearance, but if you have a biceps with a short muscle belly and a long tendon, (So that your bicep peak doesn't reach to the inside of your elbow), you can't change that shape, it's genetic.
Another example is your abdominals, the connective tissue that forms the "x pack" bulges is genetic. You may have 3, you might have 8, or whatever, but you can't change that.
Reshaping, or re-sculpting or chiseling the look of the muscles are done in various ways. First, reduction of fat. What looks like reshaping, is actually loss of fat and gain of muscles, but yes, when you have peaks on your bicep, that's a whole different story. In short, yes, whether chest, or arms, working out different sets of muscles with varied load, technique and intensity would definitely reshape them.