No need to speculate on how big or small the gaps may be, the article looks at the actual random gap values used on Wikipedia.
Quote: "The least viewed article in the sample, Erygia sigillata, has a page_random value of 0.500764585777. The article Katherine Hanley is right on its tail with a value of 0.500764582314, which is just 0.000000003 less, or 3e-9 in scientific notation. This is 98% smaller than the average random gap. In other words, Erygia sigillata is an extremely unlucky article as far as the “Random article” button is concerned! It’s 50 times less likely to be landed on than an average article."
Quote: "The least viewed article in the sample, Erygia sigillata, has a page_random value of 0.500764585777. The article Katherine Hanley is right on its tail with a value of 0.500764582314, which is just 0.000000003 less, or 3e-9 in scientific notation. This is 98% smaller than the average random gap. In other words, Erygia sigillata is an extremely unlucky article as far as the “Random article” button is concerned! It’s 50 times less likely to be landed on than an average article."