As a midwesterner, it is unethically misleading to suggest this level of efficiency to an outsider. While, yes, the welp-knee-slap is a polite and unmistakable sign that the life of this social interaction is coming to an end, that does not mean that interaction is over. The journey from “welp” to guests pulling out of your driveway can be anywhere from a 5 to 45 minute trek of baby-stepping toward the door, off the porch, down the footpath, to the car, all while tying up loose ends in conversations, corraling children (and toys, diaper bags, electronics, etc.), planning follow up meetings, last minute inquiries into various family members’ health, work and relationship status, discussions over the weather and road conditions, misremembered jokes someone heard from a guy at work, repeated offers of food or drink for the road, and assurances that either they’re not too tipsy to drive or that they “actually drive better with a buzz” while turning down offers to sleep it off… their kids may very well sit belted in the car longer while waiting for the adults to stop talking at the car door than they will for the entire drive home. The Midwestern goodbye may be one of the least efficient goodbyes every devised by man.