Goldman Sachs Research discusses the impact of UST buyback and coordinated yen-buying intervention on the USD outlook. 

"We believe that the Treasury's more activist approach to tinker with its policy tools, including last week's unusual buyback announcement as well as its prior decision to intervene in EUR/JPY, is likely also weighing on the Dollar beyond what each action implies for the policy outlook," GS notes. 

"As we wrote following the Yen intervention, unconventional policy choices can amplify questions around institutional reliability even if those policies are intended to aid market functioning. It is sensible for any bondholder to be wary if an issuer seems overly protective and sensitive to market conditions," GS adds.