I fundamentally disagree with this statement, you may not be able to build as quickly but you can definitely build.
But even going along with this model paying off your compounding, adjustable high interest rate credit card(IMF) and getting a fixed rate low interest credit card(China) is not a bad strategy.
Nigeria cannot afford to build slow because the oil is going to depreciate and run out!!!!
And I have not heard of any big loans (besides railway projects) between Nigeria and China. Jonathan has had many government projects that he has not seen to completion.
I think the short answer to all your observations is that the Military is not unified and has different factions with different loyalties. It wouldn't be unprecedented given Nigerias history of Military coups.
A good leader builds a coalition across all lines.