Sell a bass because it has a dead spot? Seems a little excessive since the new bass will eventually get one.
After two Fender Js and one Fender P, all American, Ive noticed a slight loss of sustain at some frets but nothing like a loss of sustain after a second, or even ten. But I always look for this when shopping for a new bass. My P is a 1999 and does not have a significant dead spot as defined by the OP... Diablos in your experience all basses eventually develop a noticeable dead spot as they age? Keeping my fingers crossed that mine doesn't...