Original sum of block rewards = 20,999,999.97690000 BTC
Proposed sum of block rewards = 21,000,033.29639948 BTC
So, a way to add 0.000159% inflation in a sneaky way

?
The 0.000159% is an unfortunate rounding error and is definitely unintended. But it shouldn't be hard to tweak the parameters to get to the exact number (or something within +/- a few thousand satoshis)