Interestingly, by 14 CFR 43.3(k) even the "official" method described in the article is noncompliant, as the device is removed from the aircraft, and put into a docking-station at home, loaded via RS232.
I also understand the need to follow procedures, even if there are cases in which they are clearly nonsensical or obviously without influence on air safety -- just because it's not guaranteed that everything that seems to have no influence on safety actually does have no influence on safety.
But: I had seen photographs of an old floppy drive in a B737 (I think) which was used to load updates to the FMS. Then there's a version with USB. Both storage devices could be inserted into a PC, with junk stored on them, or swapped with a completely unrelated disk/usb-stick. Inadvertently, or even with malicious intent.
So the risk of arbitrary data on the floppy drive must have been mitigated (by signing the FMS updates, checksums, ...) and considered acceptable during the design of the system.
The same, I think, should hold true for the memory card in the article: If traditionally these cards had been shipped around by postal mail, I'll claim that the possibility of damage which isn't visually apparent must have been taken into account, and a procedure been put into place, such as a CRC check to be performed after the swap, or a self-test after every turn-on of the unit. Afterwards, the card should be considered "good", independent of the method by which the data was loaded.
Does that make sense, or am I overseeing something obviously here?