Please tell me how properly twisting and crimping a connection removes that surface-to-surface connection?
Say what? "Properly twisting and crimping a connection
doesn't remove that surface-to-surface connection. That's the point. When you cut the wire and twist it back together the circuit is now being closed by surface-to-surface contact.
You do realize that for oxidation of the metal surface to occur the metal has to be exposed to an oxidizing material. A properly twisted and crimped connection will have no oxidizers around to oxidize the copper. The only way the copper will oxidize is if the person making the crimp did a very poor job of crimping the connection, and in that case it wouldn't matter if he twisted it together OR used your fold technique.
So you think that crimping a typical insulated QD terminal on wires that have been spliced together by twisting, creates an air-tight seal which prevents oxidation?
If you don't cut the wire, the only surface-to-surface contact you have to rely on is between the wire itself and the QD. As long as that QD is making solid contact with the wire at any point, the circuit will be properly closed. Even a less-than-perfect crimp which is say, only making solid contact with the wire on one side of it, will still work fine because there is no break in the wire. This amounts to a greater margin for error and is a good thing.
If you cut the wire and twist it back together, you now have to rely on surface-to-surface contact between the two ends of the cut wires themselves, and between the wires and the QD. A less-than-perfect crimp that only gets good contact on one side (usually because the other wire got pushed over and somewhat separated during the crimp), can cause problems later, even if not immediately apparent.
There is an inherent, undeniable redundancy with the "fold technique" as you call it, which means a greater margin for error.
But it boils does to this: Why cut wires that you don't have to? There are no advantages; only potential disadvantages.