With regard to exchange rates and a more general rebalancing of trade, both between the U.S. and China and more generally between high-export and high-consumption economies, two of Summers' emphases in particular are noteworthy: 1) a global rebalancing of supply and demand should be pursued through multilateral channels and institutions -- the U.S. should seek allies and so diffuse the expectation (and possibility) of gladiatorial combat between the U.S. and China over exchange rates; and 2) it's going to take time -- rebalancing the world economy is a project of years and probably decades, and yuan appreciation is only one piece in a complex (re)balancing act.
On the first point, Summers is very careful to build the multilateral context:
MW Okay, just tell me about where you are on the exchange rate question vis-a-vis China and the adjustment process vis-a-vis China.
LS The G20 made a common commitment last year in London, reiterated in Pittsburgh, to seeking more stable and balanced global growth. And I think we’ve made more progress in laying a foundation for restored global growth than has yet been made in assuring more balanced global growth - to be sure that growth, the pattern of growth over the last year, has been more balanced, with trade deficits and trade surpluses both coming down. But as the global economy recovers, it will be very important not to see a major resumption and a major widening of imbalances.