(Bloomberg) — David Roberts, a bond market veteran who built several billion-dollar funds from scratch over the past 27 years, is cutting his retirement short and buying debt again. His approach is “No AT1s. No CCCs.””  HT Image {{^userSubscribed}} {{/userSubscribed}} {{^userSubscribed}} {{/userSubscribed}} The co-manager of Nedgroup Investments’ global strategic bond fund, launched formally on Tuesday,