The test timed the 100-field form three times, then the 800-field form
three times, and compared the best of each. A busy spell on a shared
runner that fell on the second half slowed only the large form, and the
ratio went past 16x (16.6x on a gate run) though it is about 7x.
Each of five rounds now opens the small form and then the large one, and
the best round's ratio is checked against the same 16x, after one
untimed opening of each. With the values filled one by one again (the
quadratic code before #4638) it still fails, at about 48x.