Can you teach an old dog new tricks?

After working with Chessy for 3 years, Ed finaly got her to roll over. Every night I had to listen to:" Chessy can you roll over, Chessy roll over" Can you imagine listening to this for 3 years - night after night. EVERY NIGHT. Her treat for doing this was a piece of baloney. Dogs really don't want much do they. But I do have to admit that it was quite a shock to me when she finaly did "roll over". The next time the grandkids came over, Ed sat them all down and showed them Chessy's new (and only) trick. Oh, they cheered and applauded. It doesn't take much to please kids either. So now Ed is trying to get Chessy to take his socks off. I don't think we will live long enough to see that one. She just sits and looks at him. Would you pull someone's socks off with your teeth? I think its going to take more than baloney to pull that one off.