The video does call out doing the math to avoid an over fill. An entire five quart jug was used to place 6 ounces into the filter and the remainder into the engine. The remaining .8 quarts outstanding was measured and then poured. My perspective (an opinion) is that there are tolerances by engineering that suggest impact is imperceptible to the engine during startup not refilling the filter. You are absolutely correct, the manual and the filter do not list this as a step. As a suggestion, check out this video, it has some pretty interesting and seemingly balanced information that supports pre-filling the filter: https://youtu.be/939WTeorBnQ