A battle of wits with a difference this week on WireTap: Gregor has resolved to abandon his sarcastic ways and challenges Jonathan to a sarcasm-free showdown.  Who will crack first?  Plus how a call with a relaxation guru turns stressful when a crazed fan uses the Call Waiting feature to break in. That's WireTap, with Jonathan Goldstein, Sunday afternoon at 1:00 (1:30 NT, 4: PT) on CBC Radio One.