Data suggests they're not only expensive, but questionably accurate and wholly unavailable due to the stampede, with a process that will do your head in at the end, if not your nostril.

My daughter and I RAT-ed up in mid-December, before the RAT rush, and found they weren't cheap then either at $30 a pack of two, compared to free with the PCR.

You do the math. My daughter certainly did after we put the heat on her to procure them given she was travelling up from her super-spreader existence in Sydney for Christmas. Since then all existence has become a super-spreader event, so maybe that was a bit harsh.

We were looking for a quick way to kid ourselves we hadn't already passed on Covid to vulnerable family members, and looking back, those vulnerable family members were probably each other.

RATs had already earned a reputation - from scientists no less - for providing false positives, positive negatives, mild ongoing mania - the entire Covid experience in a nutshell.

But like so many people back then before Christmas, we were just trying to do the right thing and not ruin Christmas. Either by getting a test, or not getting a test. It was hard to tell, and it hasn't got much clearer.

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We figured RATs could be the exception to the rule in our case, because we'd already given Nan a hug. But little did we realise shortly after - about the time they let Covid rip - most of the rules would flip. Except that one about how easy it is to get infected.

Suddenly PCR testing was the exception, and RATs ruled. Governments knew something, you'd think, and hopefully it wasn't just that PCR testing was too fiddly and accurate and prevented people from going to work or flying interstate. Nor how expensive it would be subsidising free RATs for everyone. But still, they made it clear they wouldn't be doing that, triggering another popularity death spiral that may well extend to the polling booth but hopefully not our hospitals.

Back in December, like our governments, we welcomed the RAT as an expedient if not unreliable variation on someone else sticking a giant cotton bud up your nostril at short notice. In this way you got to do it to yourself. And when done together with your daughter over a coffee table with some ceremony, not unlike doing shots, so kind of bonding in that way, and just as expensive, with a similar reaction. Gagging, watery eyes, lots of head shaking.

But there was more to come at the end with the result. Instead of a "P" for positive, or "N" for negative, the newly initiated sovereign scientist found themselves, if things went well, confronted with a mildly alarming "C". Naturally "C for Covid" sprang to mind. OMG!!!! But no, it was actually "C for Clear" - give or take 30 per cent chance it was inaccurate. So maybe not that clear.

Hats (and mask) off to the boffin who came up with that protocol? Your dirty, dirty RAT. Talk about testing times.