The opposite is true. President Hu is undoubtedly quite in control of China and displayed his power to Gates by employing a plausible deniability ploy.
A far more likely scenario than Pomfret’s musings is that Hu is playing a cagey game. By hinting that the People’s Liberation Army made the decision without civilian knowledge, Hu is showing he is reasonable and not warlike but the test underscores China will no longer be bullied by America. Hu’s ploy of plausible deniability is in fact a common negotiating technique by the Chinese and it is surprising that Pomfret and other pundits missed that.