Diane Swonk, founder of DS Economics, says not being able to have a grown up conversation about long-term fiscal sustainability is a real issue. Prior to that, Martin Feldstein, the National Bureau of Economic Research's president emeritus, says exceptionally high asset prices are a risk to the economy. Then, Pablo Goldberg, a BlackRock portfolio manager, says it's crucial to hedge against dollar moves. Finally, Daragh Maher, HSBC's head of FX strategy, says he's still bearish on sterling.