I have a lot of overlap on this network (that was my intent) but I think maybe I am choking out the channels. I followed the advice of a GTAB KB and set my Radio 1 to channel width: "80MHz". That was a mistake from what I can tell. Putting it back down to 20MHz allowed me to get connected and pass traffic again.
I presently have all my radios set to "auto" for channel assignment, but I think it may need some intervention.
Here is a map of the area ...
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And here is a sniffer screenshot. Note that in this example, I connected to the network, and walked into the next room (notice the dip on the graph). Still connected to that same AP, but with obvious drop in quality.
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Note that channel overlap. Is that bad?