I dunno, I tend to prefer the simpler explanation which lines up with the fact that he now has an extended family. In fact, it lends more credence to the fact that he'd still be tinkering, perhaps even moreso than he did before he was active with the GBs, as retirees tend to tinker lots to keep from getting their minds idle. The fact that he could have retired isn't mutually exclusive to the fact that he could have continued tinkering. And people tend to move about, particularly after retirement. My bet is that not only did he continue tinkering, but that he'd also laid down roots.