The Serletis - Barro text that I am teaching (intermediate macro) takes the perspective that trade is ineffective at raising growth -which is mainstream thinking on the topic. Barro even mentions his face to face conversations with Bono re:Debt Jubilee 2000 and his other initiatives. He views Bono as sincere but misguided.
Bono was calling for help to be accompanied my meaningful reforms which it strikes me is the standard IMF bailout rationale and the rationale used to support transfers to the periphery in the Eurozone.
I would almost bet that most economists in favour of the latter would not be in favour of aid to Africa.
Its an interesting world.