My thoughts about accuracy
I, too, have followed some of those conversations and they seem to go 'round and 'round.
I don't know how a GPSr determines its accuracy. Nor, I suspect, would I stay awake for the explanation. Anecdotaly I can say that the alleged +/- value of the 76CSx has been smaller than the Vista C.
That said, I got this unit for three reasons (in order): auto-routing, tides, and the hope that under tree cover or in cities I'd have fewer lost receptions and less bouncing. A larger map memory was partially a consideration but I can live with what the eTrex provides.
Note that accuracy is not on the list. With goecaching I don't have any control over the waypoint that is dropped by the person placing the cache. As has been said, what fun would it be if we all had 5-decimal place accuracy?
As for creating the reference waypoint, if I went to it and found my GPSr was off by some measure, how would that knowledge help me?