My family did an audit once to find the wifi hot spots in our house. It became clear why one kid was always using the next door neighbor's wifi. The neighbor's signal was much stronger in her bedroom than it was anywhere in his house! Our signal was spotty, and completely dead where I put the family's shared computer only ten feet from the router. Wifi can be completely eccentric. Steve just went with the password that always comes to mind when these eccentricities are encountered, in the latest comic from Megacynics.
WiFi Prioritizer (free) in the Android store actually works quite well, though it's complicated and painfully non-obvious how you should adjust all the thresholds. It's a huge shame mobile devices don't have such functionality built-in...
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