If 0.01% of people are nefarious, and they check 99.9% of the time, that’s still 1/10,000,000 chance a nefarious person gets through.
As long as they don’t do this often, doing that once probably has near zero impact on security.
(Please don’t pick apart the assumptions that nefarious people always get found by screening, or that the TSA works, that’s not the point I’m making — just trying to say a one off unpredictable dropping of guard doesn’t hugely benefit nefarious actors)
If 0.01% of people are nefarious, and they check 99.9% of the time, that’s still 1/10,000,000 chance a nefarious person gets through.
As long as they don’t do this often, doing that once probably has near zero impact on security.
(Please don’t pick apart the assumptions that nefarious people always get found by screening, or that the TSA works, that’s not the point I’m making — just trying to say a one off unpredictable dropping of guard doesn’t hugely benefit nefarious actors)
Regardless of the assumption of how many people are nefarious or how actually effective TSA is, your point stands.
If they screen normally 99% of the time, then the occasional relaxing of the checks just means that the effectiveness has gone from X to 0.99*X.
TSA is security theater, but this isn’t the evidence of that.