When it started to be stated that increasing covid tests alone prevented covid, a good comparison made was that increasing pregnancy tests didn't decrease the number of pregnancies. It then had to be pointed out that decreasing the number of tests didn't decrease the number either - the number might look much lower to begin with but there would still be a surprising number of unaccountably large people in a few months time and a whole load of new people that appeared from nowhere shortly after that.
(I get that knowing someone has covid means they can isolate, thereby lowering numbers, but by that time without any other prevention they've given it to countless others).
Not exactly the same, as pregnancy is (observation notwithstanding) not catching. (As you say.)
But to get the infected into quarantine before they have used their full spreading potential (say, one or two days after infection instead of four to ten), one would have to test every day each person is meeting more than, say, one other person (logistically easiest: test at home, get a "clean for $DATE" receipt, and provide it when going to any public place. Yeah, sure.) and ideally one would *also* trace back to the spreading event and forward to contacts.
The first I simply do not see happening, when even school kids and teachers are planned to be tested once or twice a week (once they have figured out the logistics, and, sorry, but WTF?) -- and those are the people who, with crowded pubs and live venues closed, seem to me the ones making up the "most people longest time closest together least prevention" situations routinely occuring. The second ... well, it seems everyone who has *some* clue about this says it can be done only at very low incidence. Which "50 to 100" isn't.
IMO this talk about "we'll stop spreading by testing" is valium for the people. Nothing to see here, things are being done, all fine, now go out and work in whatever conditions your company considers most suitable to its bottom line, and don't forget to spend all that nice money you make...
*headdesks*
A friend has her "home" tests twice a week in her work's car park by a separate organisation. That's how reliable home testing is if it asks people who can't afford to miss work days to test in private and report the results, then relies on their managers accepting the results. Thankfully the friend has a good employer but I know many others who aren't as fortunate and who are home testing on their own.