I have heard those exact same stories about the need for atmospheric oxygen to "travel down the wire", but this whole concept does not pass my bogus internet story sniff test.
And the concern about soldering spliced wires logically seems to be based upon a worry for the potential of such a joint to separate due to the sensor's high heat environment melting the solder.
To me, the best option here is to make up jumper cables with male and female connectors which match the OEM sensor styles, made from virgin unspliced wire in a heavier gauge than OEM so to reduce resistance. Insert the wires within a heat resistant sleeve before attaching the end connectors.
My jumper cables (below) made in this manner have worked flawlessly.
Thanks - DM
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