Hermann Gottlieb's math/prediction was either flat out wrong, or the film makers ignored it, as the Kaiju did not actually follow the progression as laid out.
According to the analysis on this Discover magazine blog, if the movie had followed Hermann's predictions, the Kaiju should have won easily. The predicted curve should look like this:
With a staggering number coming through towards the end. However, in actuality the attacks appear much differently (See chart below)
Note: The article is a summation/collation of information from other websites as well, with relevant links. The relevant text before the below image of calculated frequency (as opposed to predicted) is theoretically straight from canon:
At least the novelization and official canon material of Pacific Rim are consistent in their disregard for their own mathematics. In an analysis of kaiju attack frequency over at Nerdometrics, the author catalogued all explicitly stated kaiju attacks and the time between them. He was expecting to find something similar to what I calculated—a simple and elegant exponential curve. Instead, he found this: